Prime Minister-elect Jacinda Ardern’s Labour Party and New Zealand First formally signed a coalition agreement on Tuesday, the New Zealand Herald reported. As per the agreement, New Zealand First leader Winston Peters will serve as deputy prime minister and foreign affairs minister.

Ardern came to power after the populist New Zealand First party last week said it would support her to form the government. With a 7.2% vote share in last month’s elections, Peters’ party emerged the potential kingmaker after the elections ended in a hung Parliament.

The agreement introduces several policies that focus on climate change, regional development and poverty, The Guardian reported. Banning foreigners from buying existing homes in the country, reducing immigration by 30,000 people a year and reviewing the Reserve Bank Act were among the major measures in the deal signed on Tuesday. “We will restore funding to the health system to allow access for all, ensure all Kiwis can live in warm, dry homes, take action on child poverty and homelessness,” Ardern said after the signing.

Ardern took over as the Labour Party’s chief less than three months ago. At 37, she will be the country’s second-youngest prime minister and the third woman to hold the post after Jenny Shipley and Helen Clark.