LONDON: Britain summoned Russia’s ambassador on Friday to clarify reports of a Russian military incursion into Ukraine and a build-up of equipment near the border, the Foreign Office said.

Ukraine and Russia clashed over accusations about an alleged border incursion by Russian military vehicles as a humanitarian convoy awaited permission Friday to enter Ukraine.

The military in Kiev said Russia continues to aid militants with equipment and confirmed that vehicles crossed over from its neighbor’s side under the cover of darkness Thursday night. The border violation, which Ukraine said it doesn’t consider the start of a possible invasion, was confirmed by NATO. Dmitry Peskov, a spokesman for Russian President Vladimir Putin, called the reports a “canard.”

“What we need now is clear: a de-escalation,” Ukrainian Foreign Minister Pavlo Klimkin said Friday in an interview with Bloomberg Television. “We need to stop traffic through the border, mercenaries, money, weaponry, anything. We need now to stop Russian influence.”

The standoff is adding to unease over plans by Russia, which has about 275 trucks parked near its western border loaded with what it says is humanitarian aid for rebel-held areas in eastern Ukraine. European Union governments warned Russia against using humanitarian missions as cover to bring troops into Ukraine, expressing frustration at the Kremlin’s refusal to heed calls to de-escalate the conflict.

EU ministers gathered for an emergency meeting to discuss developments in Ukraine, Iraq and Gaza. With Hungary and Slovakia calling for a reversal of sanctions imposed, the talks probably won’t lead to any new measures on Russia.