"We asked him and all his ministers to commit themselves publicly to not presenting themselves as candidates at the next elections," the former prime minister told the Corriere della Sera daily.

Berlusconi said Monti had agreed to the request in the presence of the Italian president, adding he had not spoken to each individual minister in his government.

Mario Monti was appointed last Wednesday to succeed Berlusconi, who lost his majority in parliament and stepped down under mounting pressure from Italy's worsening debt crisis.

Monti, who also holds the economy portfolio, has outlined a series of painful reforms to shore up public finances and increase competitiveness after a decade of sluggish growth.

Berlusconi reiterated that Monti must be allowed to govern until 2013 but made it clear support from his People of Freedom (PDL) party was conditional.

"Certainly if Monti takes measures that run against the line of the parties supporting him, such as the wealth tax, it won't be able to go ahead," he said.

The PDL, the biggest party in parliament, has opposed some key options in Monti's reform agenda, notably the possible levying of a wealth tax on privately held assets.

Berlusconi said his party had asked the Monti government to press for the transformation of the European Central Bank into a "guarantor of last instance" for the euro.

He said they had also asked for a commitment to review the European Union's banking regulator (EBA) norms that are "suffocating the Italian banks."

Monti, a former European Commissioner, has won the backing of all the main parties except the pro-devolution Northern League, Berlusconi's key partner in the outgoing coalition.

Berlusconi said he was sure it would be possible to maintain close ties with the Northern League. "The League is a solid and loyal ally. And the PDL is the only real ally the League will be able to count on in the future," he said.