HELSINKI (Reuters) - A Finnish lawmaker’s decision to switch parties could jeopardize the government’s reform plans and destabilize the center-right ruling coalition, whose three parties together control just 105 of the parliament’s 200 seats.

Kaj Turunen announced on Tuesday that he was leaving nationalist party Blue Reform to join its center-right coalition partner NCP, prompting a row between the parties.

Tensions within the government raise the risk that parliament could fail in June to pass major health care and local government reforms which are a cornerstone of coalition plans to eventually balance the euro zone country’s public finances.

“Why does NCP rock the boat right now?” Blue Reform leader Sampo Terho, also a minister of EU affairs, said ahead of a meeting of its 18 remaining MPs to discuss the defection. They will consider a proposal by lawmaker Matti Torvinen to quit the coalition, according to the online edition of Ilta-Sanomat newspaper.

Prime Minister Juha Sipila said last month he would dissolve the government if it failed to push through the reforms, which are expected to save 3 billion euros in annual state spending as costs rise due to Finland’s fast-ageing population.

The NCP lost a lawmaker of its own Last week, when MP Harry Harkimo quit the party to start a new political movement, saying he was opposed to the reforms. Several NCP lawmakers have criticized the reform package.

Turunen was a prominent figure in Blue Reform, which was formed last year by lawmakers who quit the nationalist Finns Party when it was kicked out of government after picking new hardline leaders.

Blue Reform kept a government seat but has lagged in opinion polls with a support of less than 2 percent.

“I started to think about this already last summer. Back then keeping up the government was more important,” Turunen told reporters on Tuesday.

Finland’s next general election is scheduled for April 2019.