The Polish, Czech, and Slovenian prime ministers will present an EU aid package for Ukraine during a visit to Kyiv on Tuesday, the Polish prime minister's top aide Michal Dworczyk said, adding that the leaders would speak on behalf of the EU.

"In Kyiv, in addition to a strong signal of support for Ukraine, a concrete support package will be presented by the prime ministers," Dworczyk said.

He said the delegation had crossed the Polish-Ukrainian border around 8.00 am CET (0700 GMT).