The planned re-election of Poland's Donald Tusk as president of the European Union is a "sign of stability" for the bloc, German Chancellor Angela Merkel said Thursday, despite bitter opposition from Warsaw.

"Today we will decide on the reelection of Donald Tusk as president of the EU for another two-and-a-half years. I see his reelection as a sign of stability for all of Europe, and I am happy to continue working with him," Merkel told the German parliament before heading to the summit of EU leaders.