The EU has proposed some of its toughest measures yet against Russia, including a total ban on oil imports and sanctions on war crimes suspects.
European Commission President Ursula von der Leyen said the package was aimed at maximising pressure on Russia while minimising damage to Europe.
Russian crude oil would be phased out within six months, she said.
Hungary has rejected the proposal as unacceptable and the Czech and Slovak governments want a transition period.
The EU has been focusing for weeks on how to wean itself off Russian oil and gas. It has already pledged to reduce gas imports by two-thirds by the end of 2022 and now plans to phase out crude oil over six months and refined products by the end of 2022.
"We will make sure that we phase out Russian oil in an orderly fashion," the Commission president said.
The package first has to be approved by EU ambassadors and is set to be signed off in the next few days.
But Hungarian government spokesman Zoltan Kovacs said his country would veto it in its current form: "They exactly know that what they are proposing is against Hungarian interests... and if we do that we are completely going to ruin the Hungarian economy."
Slovakia as well as Hungary currently relies on Russian oil and under the initial proposal would be given until the end of 2023 to find alternative suppliers. Slovakia's economy minister said his country wanted a three-year transition period, while Czech Prime Minister Petr Fiala said he would also seek a two-to-three year exemption to tackle problems with pipeline capacity.
Last year, Russia supplied the EU with a quarter of its oil imports, and the Netherlands and Germany were the biggest buyers.
The Dutch government has said it wants to halt all Russian fossil fuel imports by the end of this year and Germany has drastically reduced its reliance on Russian oil imports, down from 35% to 12%.
The UK, which is no longer in the EU, is already phasing out Russian oil, which accounts for 8% of its imports.
German Economics Minister Robert Habeck has said the six-month transition period gives Berlin long enough to make the change.
The problem for Hungary, Slovakia and the Czech Republic is that they are all landlocked and rely on their neighbours for fuel supplies. Czech special envoy for energy security Vaclav Bartuska told the BBC that Europe was currently trying to redraw the map of energy supplies as fast as it could: "We want to get rid of Russian crude once and for all and we want to be absolutely sure there'll be no need to go back and ask Russia again."
Kremlin spokesman Dmitry Peskov said Moscow was working on various options in response to the planned embargo. Sanctions were a double-edged sword for the Europeans and others, he said, as the cost for European citizens would increase every day. Oil prices rose by 5% on news of the EU plan to $110 a barrel of Brent Crude.
Ukrainian Foreign Minister Dmytro Kuleba said in a video briefing on social media that the gradual EU ban on oil was "better than nothing". Any country that opposed the oil embargo was complicit in Russia's crimes in Ukraine, he said, whatever their arguments.
Targeting war crimes and propaganda
As well as seeking a ban on Russian oil, the EU Commission president announced that sanctions would be imposed on military officers involved in suspected war crimes in Bucha and Mariupol.
"This sends another important signal to all perpetrators of the Kremlin's war: We know who you are, and you will be held accountable," Ms von der Leyen told the European Parliament on Wednesday.
There are plans for a broad ban on three of the biggest Russian state-run broadcasters.
"We have identified these TV channels as mouthpieces that amplify Putin's lies and propaganda aggressively," Ms von der Leyen said. Although the three networks were not named, they are thought to include the widely watched Russian-language Rossiya and RTR Planeta channels of state-owned operator VGTRK. The EU has already suspended two networks, RT and Sputnik, that broadcast in English, German and Spanish.
A ban would also be imposed on providing European services to Russian companies through accountants, lawyers and spin-doctors, she said.
Earlier sanctions have already hit Russian banks but the biggest bank of all, Sberbank, has been left off the list because it was considered necessary for paying for Russian gas. Sberbank makes up over a third of Russia's banking sector and is now set to be removed from the SWIFT global financial messaging system. Two other Russian banks are included in the proposals.
Previous sanctions packages have also targeted a number of individuals linked to the Kremlin and the invasion, and the head of the Russian Orthodox Church, Patriarch Kirill, is said to be on the latest list. He has given his full support to the war, prompting Pope Francis to warn him not to become "Putin's altar boy".
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'We want Ukraine to win'
The Commission president also gave details of plans to help Ukraine tackle the vast costs of the war and the impact on its economy.
Explaining Europe's "very special responsibility towards Ukraine", she said Ukraine needed to fund the dramatic fall in its economic output and wider reconstruction.
A recovery package would be drawn up that could tackle weaknesses in the Ukrainian economy and help fight corruption, she said.
"We want Ukraine to win this war, but we also want to set the conditions for Ukraine's success in the aftermath of the war."
In a separate move, the EU also promised to increase military aid to neighbouring Moldova, which is under threat from Russian soldiers based in the breakaway Moldova region of Transnistria. "We will continue to deepen our partnership with you to bring your country closer to the EU," European Council President Charles Michel told Moldova's pro-EU president, Maia Sandu, in Chisinau.
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