Greek Prime Minister Alexis Tsipras said Friday that ultimatums and blackmail had no place in the EU as he tried to seal a crucial debt deal with creditors demanding tough austerity reforms in return.

"Europe's principles are not based on blackmail and ultimatums," Tsipras said after a two-day EU leaders summit dominated by the Greek debt crisis. "In these crucial hours, nobody has the right to put these principles at risk."