Marek Belka lost an earlier confidence vote held on 14 May

The lower house of parliament voted 235 to 215, with one abstention, in support of Mr Belka and his leftist government.

Mr Belka became prime minister when his predecessor, Leszek Miller, resigned the day after Poland was admitted to the European Union on 1 May.

Early elections would have been held in August had Mr Belka, a former World Bank adviser, not been approved.

Mr Belka, 52, had already lost one vote of confidence on 14 May, but stayed on as caretaker leader.

He only squeezed through this time with the help of a left-wing splinter group.

Governing bloc's woes

He is a member of the governing Democratic Left Alliance (SLD), which has seen its popularity plummet in its three years in office amid high unemployment and struggling health system.

But unlike Mr Miller, he was never an SLD leader.

Belka is a good message for Europe Polish MEP Janusz Onyszkiewicz

Mr Belka has served previously as deputy prime minister and finance minister.

His endorsement was welcomed as "a good message for Europe" by Janusz Onyszkiewicz, Polish MEP and former defence minister.

"He will be treated as a serious partner, even though this is just a temporary government.

"The most important thing for him to do now is to temper the discussion about the [EU] constitutional treaty in the country."

He added his endorsement would hinder the rise of anti-EU populist voices.

"They will make a lot of noise but they won't really harm Poland's reputation", he added.

In a speech to deputies earlier, the prime minister said he would submit to a new confidence vote later in the year if he was backed on Thursday.

"I ask for your investiture," he said.

But he added: "Seven days after the constitutional deadline for submitting next year's budget to the parliament I will ask for a new vote of confidence.

"I do not intend to govern without a parliamentary mandate."