M5S snub of key vote plunges Italian government into crisis.

Italy's president Sergio Mattarella refused to accept the resignation of prime minister Mario Draghi on Thursday night after the populist MoVimento 5 Stelle (M5S) pulled out of a key confidence vote in the coalition government.

Mattarella has invited Draghi to take stock of the political situation, according to a statement from the president's office, with the premier set to report to parliament next Wednesday.

Draghi tended his resignation after the M5S, led by former premier Giuseppe Conte, failed to back a crucial vote on a €26 billion cost-of-living package in the senate on Thursday.

The decree also included plans for a waste-to-energy incinerator in Rome, a proposal opposed by the M5S, the second largest partner in the national unity government.

• Italy's government risks collapse as M5S threatens to boycott key vote

In the end Draghi won Thursday's confidence vote, which was passed with 172 votes in favour and 39 against.

However the premier had previously warned that he would not govern without the backing of the M5S and promptly set off to the Quirinal Palace to offer his resignation to President Mattarella.

Draghi's broad coalition, formed in early 2021 after the collapse of Conte's second executive, has had the support of all major parties in parliament with the exception of the right-wing Fratelli d'Italia (FdI) whose leader Giorgia Meloni has called for immediate elections, ahead of the scheduled general election in spring 2023.

Conte claims the government has refused to listen to proposals from the M5S which is opposed to Italy sending more military aid to Ukraine.

Support for the M5S has plunged over the last year and recently the party was split after foreign minister and former leader Luigi Di Maio quit, taking around 60 parliamentarians with him.

Di Maio on Thursday described the move by M5S as an attempt to "launch a nine-month election campaign to improve their standings in the polls".