Poland's President Aleksander Kwasniewski re-appointed Marek Belka as prime minister on Friday, giving his left-wing ally a final chance to win a parliamentary mandate and avoid early elections in August.
Belka lost a first parliamentary confidence vote last month but has stayed on as caretaker.
Still, the political stalemate has halted work on key fiscal reforms.
"We need a stable, well-functioning government, which could pursue transparent policies...I am convinced that Marek Belka's cabinet is the best solution for Poland," Kwasniewski said at a short ceremony. He will swear in the new cabinet at 1100 GMT.
Parliament has two weeks to hold a confidence vote, in which Belka needs a simple majority to win, not the qualified majority needed in the first attempt.
The minority ruling Democratic Left Alliance (SLD) needs to find around 40 more votes in the 460-seat lower house to ensure Belka gains the parliamentary mandate. If Belka loses, general elections will be held in mid-August, a year before schedule.
To win, Belka must gain support from the Social Democracy of Poland (SDPL), an opposition party of SLD rebels with 33 seats.
The SDPL wants elections this year in exchange for their support, but a poor showing in Sunday's European Parliament elections may weaken their resolve to speed up the polls.
Opinion polls show support for the SDPL on the verge of the five percent threshold needed to gain representation in the EU parliament and the SLD around eight percent. But low voter turnout expected on Sunday may skew election results.