Romania's ruling party plans to extend voting in a referendum on whether to impeach the president to two days from one, a senior politician said, seeking to boost voter turnout in the effort to drive him out.

Leftist Prime Minister Victor Ponta's campaign against conservative President Traian Basescu has drawn criticism from the EU which sees a threat to democratic rule of law in the Balkan state.

Ponta says he wants Basescu out because the president has improperly opposed the government economic reforms and for abusing his post by bending its powers to assist his allies.