Ukraine crisis: Timeline
For months, pro-Russian separatists have fought Ukrainian forces in two eastern regions of Ukraine but a ceasefire has been agreed by both sides.
The pro-Russian rebellion began in Donetsk and Luhansk in April, inspired by Russia's annexation of the Ukrainian peninsula of Crimea weeks before.
The separatists in the predominantly Russian-speaking east were enraged by the overthrow of elected pro-Russian President Viktor Yanukovych, who fled Ukraine after weeks of protests against his decision not to sign an Association Agreement with the European Union.
Here is a timeline of events in the most dangerous conflict to grip Europe since the wars in the former Yugoslavia.September 2014
9 September: Dutch experts find that Malaysia Airlines flight MH17 broke up in mid-air after being hit by "objects" that "pierced the plane at high velocity" in July. Correspondents say this matches claims that MH17 was hit by missile shrapnel. The 5 September ceasefire is largely holding, but the EU formally adopts new sanctions on Russia, with no word on when they will be put in place.
8 September: Shelling near Donetsk airport raises fears that the ceasefire may collapse.
5 September: Ukraine and pro-Russian rebels in the east sign a truce deal to end almost five months of fighting.
4 September: Nato, at its summit in Wales, says it "stands with Ukraine" in the face of Russia's "destabilising" influence.
3 September: Russian President Vladimir Putin sees a peace deal between Ukraine and the rebels by 5 September, after talking to President Petro Poroshenko of Ukraine by phone. US President Barack Obama visits Estonia to reassure the Baltic states of Nato support. Under pressure from Nato allies, France says conditions are "not right" for delivery of the first of two Mistral navy assault ships to Russia.
2 September: Russia is to alter its military strategy as a result of the Ukraine crisis and Nato's presence in eastern Europe, a top Russian official says. The newly designated EU foreign affairs chief, Federica Mogherini, says Nato countries bordering Russia need more than a paper pledge that Nato will help them in a crisis.
1 September: Ukraine says 700 of its men have been taken prisoner as pro-Russian rebels advance in the east. Government forces retreat from Luhansk airport. Nato announces plans for a rapid response force to protect Eastern European members against possible Russian aggression.August 2014
31 August: Russian President Vladimir Putin calls for talks to discuss "statehood" for eastern Ukraine. Ten Russian paratroopers captured inside Ukraine are exchanged for 63 captured Ukrainian soldiers. The EU gives Russia one week to reverse course in Ukraine or face new sanctions.
29 August: The crisis in eastern Ukraine is "slipping out of control" and needs to be reined in to avoid direct military confrontation between Ukraine and Russia, Germany warns.
27-28 August: Rebels open up a new front, capturing the town of Novoazovsk on the Sea of Azov, a few miles inside the Russian border. Ukrainian President Petro Poroshenko accuses Russia of moving troops into Ukraine. Rebel leader Alexander Zakharchenko says there are 3-4,000 Russian civilians in their ranks, including many soldiers on leave.
26 August: Ukraine releases videos of captured Russian paratroopers, two days after rebels parade captive Ukrainian soldiers through the streets of Donetsk. Russia says the paratroopers crossed the border by accident. Meanwhile, some 100 wounded Russian servicemen are reportedly airlifted to hospital in St Petersburg. President Vladimir Putin meets Mr Poroshenko in Belarus, in their first direct talks since early June.
22 August: A convoy of more than 100 Russian lorries enters Ukraine without permission, carrying what Russia says is humanitarian aid for the besieged city of Luhansk.
18 August: A convoy of refugees from the Luhansk area is hit by rockets leaving women and children dead. Rebels deny carrying out the attack.
6 August: Russian President Vladimir Putin hits back against Western sanctions, with a "full embargo" on fruit, vegetables, meat, fish, milk and dairy imports.
5 August: As heavy fighting erupts in Donetsk city, the UN says more than 1,000 civilians are fleeing the conflict zone every day.
3 August: Ukrainian forces have virtually surrounded the city of Luhansk. The city's supplies of power and water supplies run low and communications are down.July 2014
30 July: The EU and US announce new sanctions against Russia with focus on oil sector, defence equipment and sensitive technologies.
21-23 July: The first remains of victims of the MH17 disaster are moved by train to Kharkiv. Two days later two planes carrying bodies arrives in the Netherlands.
17 July: Malaysia Airlines flight MH17 from Amsterdam is shot down near the village of Grabove in rebel-held territory close to the border with Russia. A total of 298 people are killed including 80 children. Western nations said the plane was hit by a Russian-supplied SA-11 missile fired by rebels.
14 July: A Ukrainian An-26 military transport aircraft is shot down close to the Russian border at a height of 6,500m (21,325ft), with Ukrainian officials alleging it was a Russian missile.
11-12 July: A rebel rocket attack on a village near Russian border in Luhansk region leaves at least 20 soldiers dead. As Ukrainian troops close in on Donetsk, rocket fire kills four civilians.
5 July: Rebels abandon their command centre at Sloviansk in the face of a government offensive.June 2014
27 June: The EU signs an association agreement with Ukraine in what President Petro Poroshenko describes as the most important day in the country's history since independence in 1991.
25 June: Russia's parliament cancels a parliamentary resolution authorising the use of Russian forces in Ukraine. EU leaders welcome the move but warn of more sanctions.
23 June: Rebels agree to observe the ceasefire proposed by the government until 27 June but ceasefire falls apart a week later.
20 June: President Poroshenko declares a week-long truce.
14 June: A violent protest outside the Russian embassy in Ukraine leads to windows being smashed and cars being overturned. Pro-Russia separatists shoot down a military plane in the east, killing 49 people.
13 June: Government troops win back the port city of Mariupol after heavy fighting.
12 June: Ukraine says three Russian tanks have entered rebel areas in the east. Russia denies the allegations.
10 June: Petro Poroshenko, sworn in on 7 June, orders the creation of humanitarian corridors so civilians can flee areas of east Ukraine hit by conflict.
6 June: Russian President Vladimir Putin and Ukrainian President-elect Petro Poroshenko meet in France and call for a quick end to the bloodshed.
4 June: Separatist rebels take two Ukrainian military bases in the eastern region of Luhansk.
3 June: Nato pledges to bolster its defence capabilities in response to Russian actions in Ukraine.May 2014
29 May: Pro-Russian rebels shoot down a military helicopter near Sloviansk, killing 14 people including a general.
26-27 May: Ukrainian army launches "anti-terrorist operation" to oust separatists occupying Donetsk airport. Combat jets, helicopters and airborne troops deployed and at least 40 separatists killed.
25 May: Ukraine holds presidential election but most polling stations in east remain closed. President-elect Petro Poroshenko vows to bring "peace to a united and free Ukraine".
22 May: Rebel attack on checkpoint in Volnovakha, east Ukraine, leaves 14 soldiers dead.
19 May: Russia's President Vladimir Putin says he has ordered troops near Ukraine's border to withdraw, but Nato says there is no sign they have pulled back.
11 May: Pro-Russian separatists in Donetsk and Luhansk declare independence after referendums which were not recognised by Kiev or the West.
7 May: In an apparent shift in Russian policy, President Putin calls for referendums in eastern Ukraine to be postponed to encourage dialogue. He also describes Ukraine's presidential elections scheduled for 25 May as a move "in the right direction".
4 May: Pro-Russian protesters attack the police headquarters in Odessa, prompting police to release dozens of people arrested over the earlier unrest.
2 May: Clashes in the Black Sea city of Odessa leave at least 42 people dead, most of them pro-Russian activists killed when a building they had barricaded themselves inside caught fire.
1 May: Acting President Olexander Turchynov reinstates conscription, warning Ukraine is on "full combat alert". Pro-Russians take over the regional prosecutor's office in eastern Donetsk.April 2014
22 April: Ukraine's acting president orders the relaunch of military operations against pro-Russian militants in the east after two men, one a local politician, are found "tortured to death" in Donetsk region.
20-21 April: The shooting of three people manning a pro-Russian checkpoint near Sloviansk outrages Russia, which blames it on Ukrainian nationalists.
17 April: Russia, Ukraine, the US and the EU say they have agreed at talks in Geneva on steps to "de-escalate" the crisis in eastern Ukraine. Three people are killed when Ukrainian security forces fend off a raid on a base in Mariupol.
16 April: The "anti-terrorist" operation quickly stalls: pro-Russian militants in eastern Ukraine seize six armoured vehicles in the town of Kramatorsk.
15 April: Ukraine's acting President, Olexander Turchynov, announces the start of an "anti-terrorist operation" against pro-Russian separatists.
12 April: In eastern Ukraine, occupations of official buildings by pro-Russian protesters and militants multiply.
11 April: Ukraine's Interim Prime Minister Arseniy Yatsenyuk offers to devolve more powers to the eastern regions, as pro-Russia occupations in Donetsk and Luhansk continue.
7 April: Protesters occupy government buildings in the east Ukrainian cities of Donetsk, Luhansk and Kharkiv, calling for a referendum on independence. Ukrainian authorities regain control of Kharkiv government buildings the next day.March 2014
28 March: Amid signs of a big build-up of Russian forces on Ukraine's eastern border, US President Barack Obama urges Moscow to "move back its troops" and lower tensions.
18 March: President Putin signs a bill to absorb Crimea into the Russian Federation.
17 March: The EU and US impose travel bans and asset freezes on several officials from Russia and Ukraine over the Crimea referendum.
16 March: Crimea's secession referendum on joining Russia is backed by 97% of voters, organisers say.
1 March: Russia's parliament approves President Vladimir Putin's request to use force in Ukraine to protect Russian interests. Pro-Russian rallies are held in several Ukrainian cities outside Crimea.February 2014
27-28 February: Pro-Russian gunmen seize key buildings in the Crimean capital, Simferopol. Unidentified gunmen in combat uniforms appear outside Crimea's main airports. At his first news conference since fleeing to Russia, Mr Yanukovych insists he remains president.
23-26 February: Parliament names speaker Olexander Turchynov as interim president. An arrest warrant is issued for Mr Yanukovych. Arseniy Yatsenyuk is nominated prime minister. The elite Berkut police unit, blamed for deaths of protesters, is disbanded.
- President Yanukovych disappears
- Protesters take control of presidential administration buildings
- Parliament votes to remove president from power with elections set for 25 May
- Mr Yanukovych appears on TV to denounce "coup"
- His arch-rival Yulia Tymoshenko is freed from jail
21 February: President Yanukovych signs compromise deal with opposition leaders.
20 February: Kiev sees its worst day of violence for almost 70 years. At least 88 people are killed in 48 hours. Video shows uniformed snipers firing at protesters holding makeshift shields.
18 February: Clashes erupt, with reasons unclear: 18 dead, including seven police officers, and hundreds more wounded. Some 25,000 protesters are encircled in Independence Square.
14-16 February: All 234 protesters arrested since December are released. Kiev city hall, occupied since 1 December, is abandoned by demonstrators, along with other public buildings in regions.January 2014
28-29 January: Prime Minister Mykola Azarov resigns and parliament annuls the anti-protest law. Parliament passes amnesty bill promising to drop charges against all those arrested in unrest if protesters leave government buildings. Opposition rejects conditions.
16-23 January: Parliament passes restrictive anti-protest laws, Days later two people die of gunshot wounds as clashes turn deadly for first time. Third death reported as the body of high-profile activist Yuriy Verbytsky is found. Protesters begin storming regional government offices in western Ukraine.December 2013
17 December: Vladimir Putin throws President Yanukovych an economic lifeline, agreeing to buy $15bn of Ukrainian debt and reduce the price of Russian gas supplies by about a third.
Early December: Protesters occupy Kiev city hall and Independence Square in dramatic style, turning it into a tent city. Biggest demonstration yet sees 800,000 people attend demonstration in Kiev.
Late November: Protests gather pace, as 100,000 people attend a demonstration in Kiev, the largest in Ukraine since the Orange Revolution. Police launch first raid on protesters, arresting 35.
21 November: President Yanukovych's cabinet abandons an agreement on closer trade ties with EU, instead seeking closer co-operation with Russia. Ukrainian MPs also reject a bill to allow Yulia Tymoshenko to leave the country. Small protests start and comparisons with the Orange Revolution begin.2010
February: Viktor Yanukovych is declared the winner in a presidential election judged free and fair by observers. His main rival, Prime Minister Yulia Tymoshenko, is arrested for abuse of powers and eventually jailed in October 2011.2004
December: Opposition candidate Viktor Yushchenko tops poll in election re-run. Rival candidate Viktor Yanukovych challenges result but resigns as prime minister.
November: Orange Revolution begins after reports of widespread vote-rigging in presidential election nominally won by pro-Russian candidate Viktor Yanukovych. Opposition candidate Viktor Yushchenko leads mass street protests and civil disobedience. Supreme Court annuls result of poll.1991
August: Ukrainian parliament declares independence from USSR following attempted coup in Moscow. In a nationwide referendum in December, 90% vote for independence.