Italy's president is facing calls for his impeachment after refusing to appoint a key minister backed by the country's prospective prime minister.

Sergio Mattarella would not endorse Eurosceptic Paolo Savona as economy minister, despite him being supported by Giuseppe Conte - who was picked as a compromise prime ministerial candidate by the populist coalition hoping to form a government.

Mr Conte, a little-known 53-year-old lawyer with no political experience, subsequently rejected Mr Matteralla's offer to form an administration - throwing Italy into fresh political crisis.

The country has been without a government since elections on 4 March left the Eurosceptic 5-Star Movement and the right-wing League Nord as the two largest parties in a hung parliament.

Mr Mattarella summoned Carlo Cottarelli, a former economist with the International Monetary Fund, for talks on Monday as he moved to appoint a technocratic government ahead of new elections.


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Image: League Nord party leader Matteo Salvini wanted a Eurosceptic economy minister

The leaders of both 5-Star and the League denounced the president's actions and signalled they will not support the appointment of Mr Cottarelli.

"They've replaced a government with a majority with one that won't obtain one," 5-Star leader Luigi Di Maio told supporters at a rally near Rome.

Dubbed "Mr Scissors", 64-year-old Mr Cottarelli worked at the IMF from 2008 to 2013 and is known for making cuts to public spending in Italy.

League Nord leader Matteo Salvini dimissed Mr Cottarella as "Mister Nobody" who "represents financial institutions".

Mr Matterella accepted every proposed minister by the hopeful 5-Star and League Nord coalition apart from Mr Savona, who has previously said Italy needs a plan to quit the euro "if necessary" and branded the EU's single currency as a "German cage".

The euro jumped in value on the president's veto.

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Image: 5-Star Movement leader Luigi Di Maio branded the president's actions 'unacceptable'

Explaining his decision to reject university professor Mr Savona, Mr Matterella claimed the appointment would have spooked financial markets.

He said: "I asked for the [economy] ministry an authoritative person from the parliamentary majority who is consistent with the government programme... who isn't seen as a supporter of a line that could probably, or even inevitably, provoke Italy's exit from the euro."

Prior to the president's intervention, Mr Conte had been in line to lead the first populist regime in western Europe.

Announcing the end to his efforts to lead a government, Mr Conte said in an address on Sunday: "I have rejected the mandate to form a government that was offered to me by President Mattarella.

"I thank the president for giving me the mandate on 23 May and I thank the people from the main political forces, Luigi Di Maio from the 5-Star Movement and Matteo Salvini from the League to have put my name forward.

"I can assure you I have used maximum efforts and attention for this task and I can assure you that I have worked in a climate of maximum collaboration with those political forces."

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A furious Mr Di Maio immediately called for action against the president's "unacceptable" actions and suggested ratings agencies and financial lobbies might as well appoint Italian governments as voting was "pointless".

"We were a few steps away from forming a government, and we were stopped because in our cabinet there was a minister who criticised the EU," he said.

"I want this institutional crisis to be taken to parliament and the president tried."

Mr Salvini raised the prospect of new elections as he raged that Italy wasn't a "colony" and "won't have Germany tell us what to do".

Image: Giuseppe Conte had been expected to become Italian PM

Any efforts to impeach Mr Matterella would be filed under article 90 of the Italian constitution, which would see MPs vote on whether he had committed "high treason" or "attacked the constitution".

If a simple majority votes in favour, the constitutional court would then be called to decide whether to impeach or not.

Responding to the dramatic development, caretaker prime minister and Mattarella supporter Paolo Gentiloni said: "Now we must save our great country."

Finance bosses have expressed concern at the economic agenda of Italy's proposed coalition, which could see tax cuts and boosted government spending, as the country continues to struggle with huge national debt.

The European Central Bank has warned Italy to stick to EU budget rules, while Goldman Sachs told clients: "The new coalition government proposes measures which our economists see as likely to widen the budget deficit and lead Italy's national debt to rise again."