Paris - The European Union again failed to agree to an oil embargo against Russia Monday as part of a sixth package of sanctions over the war in Ukraine. Hungary remains a key holdout, demanding a high price for greenlighting the package.

Signs of exasperation against Hungary emerged at a meeting of European Union foreign ministers in Brussels - including from Ukraine's top envoy Dmytro Kuleba, who was invited to the talks. An oil embargo against Russia, he said, was essential.

"It's clear who's holding up the issue,' Keleba said. 'But time is running out because every day, Russia keeps making money and investing this money into the war.'

Lithuanian Foreign Minister Gabrielius Landsbergis also expressed frustration.

"Now, unfortunately, we are - the whole union is being held hostage by one member state which cannot help us find a consensus."

The EU needs unanimous agreement from its 27 members to push through each set of sanctions. Until now, that's happened. An oil embargo would be the toughest sanction so far-hurting Moscow's ability to finance the war.

It would also hit some European countries highly dependent on Russian energy. But Hungary - already considered an EU maverick on other issues - is especially putting on the brakes. Reports say Budapest wants hundreds of millions of dollars in compensation, and possibly more, to transition from Russian oil imports.

EU Foreign Policy chief Josep Borrell said the conversations with Hungary were largely technical. He offered no timeline for coming to an agreement. Still, some EU members are hopeful that a breakthrough is only days or weeks away.

"One thing is clear - I think it's clear for everyone in the council: We have to get rid of the energy dependency of the European Union with respect to oil, gas and coal coming from Russia," Borrell said.

Borrell said the war in Ukraine has tested the bloc in key ways, not just the conflict itself. But it is also testing Europe's energy resiliency as it unwinds its dependency on Russian supplies - and its very legitimacy.