Stavros Theodorakis, leader of the centrist To Potami party, will meet with conservative Prime Minister Antonis Samaras on Wednesday at 6 p.m.
It will be the first official meeting between the two leaders. Scheduled talks between the two were cancelled in October after Samaras called for a confidence vote.
Talks Wednesday are expected to focus on To Potami's demand for a change to Greece's electoral law as well as the constitutional review proposed by the New Democracy-led administration.
Recent surveys have shown To Potami polling at third place with up to 10 percent of the vote. The party won 6.6 percent of the vote in May's European elections, electing two representatives at the Brussels-based Parliament.