Right-wing League leader Matteo Salvini's drive for early elections in Italy hit a road bump on Monday with parliamentary party leaders failing to decide when the Senate should debate his no-confidence motion in the government.

The deeply-divided parliamentary chiefs ordered the full upper house Senate to break its summer recess on Tuesday to decide for itself on when to hold the vote, which looks set to trigger the downfall of Prime Minister Giuseppe Conte.

Salvini, now interior minister in a year-old coalition with the anti-establishment Five Star Movement, wants to capitalize on his surging popularity in the opinion polls and hold a new election that could see him crowned as prime minister.

Read more:

Italy hurtles into new crisis

But Five Star and many lawmakers from the opposition center-left Democratic Party (PD) are furious over Salvini's maneuvering and want to slow his charge to the ballot box, saying this will torpedo key bills and damage Italy’s fragile finances.

"You will see that Italians will make the League pay for the stab in the back it has dealt Italy," Five Star leader Luigi Di Maio said on Facebook.

Di Maio ruled out rumors that he might hook up with former PD Prime Minister Matteo Renzi to form an alternative coalition. But looking to play for time, both the Five Star and PD said Conte should address parliament on August 20 over the crisis and not August 14, as the League has demanded.

The Senate will set the calendar for the unprecedented summer political crisis at a session due to start on Tuesday evening.

Italy's parliament is normally closed for most of August and the country has not held a national election in the autumn for a century because it is the time the government traditionally uses to draw up the budget – an elaborate, time-consuming process.

Ahead of the Senate session, Salvini is expected to meet former center-right Prime Minister Silvio Berlusconi, who leads Forza Italia, to discuss reviving a long-standing electoral pact between their two parties.

The anti-EU Salvini said this year that he wanted to break free from the pro-European Berlusconi. However, Forza Italia politicians could try to use their numbers in parliament to block any rush to early elections if Salvini spurns them.

Salvini, photographed at the weekend posing for shirtless selfies with supporters at the beach, has dominated Italian politics since forming a government with Five Star. He has campaigned non-stop, promoting a "man-of the people" image and touting a popular clampdown on illegal immigration.

However, some League voters have been dismayed by his decision to sink the government and have voiced dissent on social media. Salvini was booed and heckled during campaign stops in Sicily on Sunday.

His move to ditch the coalition also raised the government's cost of borrowing and sparked a sell-off in shares.

On Monday the spread between Italian benchmark bonds and safer German Bunds stood at 230 basis points, some 30 points higher than where it had stood before Salvini's surprise decision on Thursday.