The European Union president is opening consultations with EU leaders to consider new steps to pressure separatists in eastern Ukraine and Russia to stick to last week's peace agreements.

EU President Donald Tusk said Friday there had been "more than 300 violations" of the ceasefire which was supposed to kick in last weekend.

He said that the EU is clearly "reaching a point when further diplomatic efforts will be fruitless unless credibly backed up by further action."

The 28-nation bloc already has imposed visa bans and asset freezes on 151 separatists and Russian officials while 37 entities are now also hit with restrictive measures. It also has targeted economic and financial sanctions in place against Moscow.

The EU is now in a process of assessing further sanctions.