Ukraine border guards to inspect Russian aid convoy
Ukrainian border guards have arrived to inspect a controversial Russian aid convoy parked at the frontier.
The convoy aims to bring aid to cities in eastern Ukraine held by pro-Russian rebels, although reporters said many of the lorries were largely empty.
Ukraine fears the convoy may carry military supplies for the rebels, an accusation Russia has rejected.
Meanwhile Nato on Friday condemned what it said was an "incursion" into Ukraine by Russian military vehicles.
On Thursday, two reporters had said they saw Russian army vehicles heading into Ukraine.
Nato Secretary General Anders Fogh Rasmussen said: "We see a continuous flow of weapons and fighters from Russia into eastern Ukraine, and it is a clear demonstration of continued Russian involvement in [its] destabilisation."
The UK Foreign Office summoned Russian Ambassador Alexander Yakovenko "to clarify reports of Russian military incursion".
The Ukrainian military said its forces had engaged an armoured column and partially destroyed it.
Russia's government has consistently denied directly arming or training the rebels, who sparked the conflict in April when they took control of several cities in eastern Ukraine.'Likely to take time'
Ukrainian officials had been quoted as saying the inspection had already begun, but later on Friday Ukrainian national security spokesman Andriy Lysenko told Ukrainian TV that the inspectors were still waiting for the relevant paperwork from the International Committee of the Red Cross (ICRC).
The head of mission of the Organisation for Security and Cooperation in Europe (OSCE), Paul Picard, confirmed to the BBC that the inspection had yet to begin.
The BBC's Steve Rosenberg, who has been following the convoy, says some of the lorries were opened up for the media on Friday, and the main thing that struck him was how empty many of the vehicles were.
The ICRC's Head of Operations for Europe and Central Asia, Laurent Corbaz, said: "The agreement... foresees that the trucks will be checked by the customs officers of Ukraine on Russian territory and then be allowed inside Ukraine with ICRC people accompanying the convoy and then unload somewhere in Luhansk and go back to Russia, empty."
He said that given the size of the cargo and the security constraints, "implementation is likely to take some time", not in one week and possibly "much longer".
Sergey Karavaytsev, head of the international activities department of Russia's emergencies ministry, told the RIA Novosti news agency he expected the trucks to be in the same place "for a few more days".Putin visit
Luhansk, a rebel stronghold, saw heavy shelling on Thursday, as did Donetsk, which is also held by rebels.
The conflict, which has claimed more than 2,000 lives, has intensified in recent weeks.
The violence began when pro-Russian rebels seized government buildings and tried to declare independence.
The military launched an operation to retake the east, and stepped up its activities in June.
Russian President Vladimir Putin on Thursday visited Crimea, which Russia annexed from Ukraine in March in a move that drew international condemnation.
Ukraine said it had officially protested to Russia over the visit, saying it was an affront to Ukraine's sovereignty.
Mr Putin said Russia's goal was "to stop bloodshed in Ukraine as soon as possible".
He said Russia should not "fence itself off from the outside world" although he said Russia would "not allow anyone to treat us with arrogance".
On Thursday it emerged that Russia's largest oil company, Rosneft, had asked the Russian government for a loan of more than $40bn (£24bn) in order to help it weather the impact of Western sanctions.