KIEV, Feb 21 (Reuters) - Talks on Ukraine's crisis that are being brokered by three European Union ministers are proving difficult and will continue later on Friday after a break of a few hours, a European diplomatic source said.
"The negotiations are very difficult and went on all through the night," the source said. "There is a break now. The participants will come back together again before midday."
(Reporting by Sabine Siebold, Editing by Timothy Heritage)