Ukrainian President Volodymyr Zelenskyy on Sunday called the coming week "historic", with the European Commission's recommendation that Ukraine become a candidate for membership to be discussed by leaders of the 27-nation bloc.
Zelenskyy said it would be among the most "fateful" decisions in Ukraine's history.
The war has increased pressure on EU governments to fast-track Ukraine’s candidacy, but the process is expected to take years, and EU members remain divided over how quickly and fully to welcome new members.
At the same time, Zelenskyy said that Kyiv was expecting increased Russian hostilities this week and was warning its partners.
"Obviously, we should expect greater hostile activity from Russia. Purposefully - demonstratively. This week exactly. And not only against Ukraine, but also against other European countries," the president said.
"We are preparing. We are ready. We are warning partners."
Zelenskyy said "fierce fighting" continued in Donbas but that places such as Sievierodonetsk and Lysyhansk were "holding on".