European Union foreign ministers are deploring what they say is more Russian interference in Ukraine, but hoping an end to the crisis can still be peacefully negotiated.

The 28 ministers, meeting Monday in Luxembourg, could add more names to a list of Russian officials whose assets in EU member nations have been frozen. But a dramatic ratcheting up of the trade bloc's sanctions against Russia isn't expected.

Frans Timmermans, the Dutch foreign minister, told reporters: "I think it would be too early today. But I think we need to be well prepared."

British Foreign Secretary William Hague said the well-coordinated actions of armed pro-Russian groups in eastern Ukraine during the previous 48 hours left no real doubt "this is something that is being planned and brought about by Russia."