Italian Prime Minister Mario Draghi said on Tuesday he would leave office if the 5-Star Movement pulls out of his coalition, and called on parties supporting him to stop launching "ultimatums" to his government.
5-Star leader and former Prime Minister Giuseppe Conte last week tabled a list of policy demands to continue backing the government and threatened to quit if Draghi failed to enact a series of measures.
A crucial vote of confidence on a stimulus package to help families and firms cope with the energy crisis will take place in the Senate this week, and it is still unclear whether the 5-Star will participate in the vote or leave the coalition.
On Monday, the party raised the stakes, deciding not to vote in favour of the decree at the lower house of parliament.
Looking to ease tensions, after a meeting with trade unions Draghi said that many of the policy priorities of the 5-Star Movement overlapped with those of the government, but warned against continuous demands from coalition partners.
"A government does not work with ultimatums, it loses the point of its existence," Draghi told a news conference, adding he will not be willing to carry on as prime minister if 5-Star pulls out.
Rightist League leader Matteo Salvini, whose party is the biggest in Draghi's coalition, last June also said he will decide in September whether to remain in or not.
Draghi said his cabinet would move to implement a minimum wage, one of the 5-Star's key demands, and also said he would cut taxes on wages.
5-Star leader Conte summoned a gathering of the party's senior figures for Wednesday at 8.30 a.m. (0630 GMT) to outline his position on the measures the government discussed with the unions, a statement said.
The government has approved measures worth around 33 billion euros ($33.22 billion) since January to shield the economy from rising prices and surging energy costs. Another decree with fresh help will be passed at the end of July, Draghi said.
"We must take action to support employment and address inequalities that are worsening at this time, and we must defend pensions and wages", Draghi said.
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(Reporting by Angelo Amante and Giuseppe Fonte; editing by Gavin Jones and David Evans)