Portugal's shortest-ever government is moving out of office, making way for an untested anti-austerity alliance that has yet to explain how it will increase spending without damaging the eurozone country's public finances.

Outgoing Prime Minister Pedro Passos Coelho was due to formally present his resignation to the Portuguese president Wednesday, a day after the leftist alliance forced out his center-right government in a parliamentary vote.

The outgoing government won an October general election. But the second-placed Socialist Party forged a pact with the Communist Party and radical Left Bloc to create an outright parliamentary majority. Socialist leader Antonio Costa is expected to be the next prime minister.

The disagreement is over whether to continue with austerity policies begun when debt-heavy Portugal needed a 78 billion-euro ($84 billion) bailout in 2011.