ROME - Italy's rightwing League party and the populist Five Star Movement want law professor Giuseppe Conte to lead their coalition as Italy's next prime minister in a prelude to forming a new government, the two parties told President Sergio Mattarella on Monday.

Mattarella may summon the little-known academic to the presidential palace and officially confer on him a mandate to form a new government as early as Tuesday morning.

Together, they will discuss a cabinet line-up, and then the new government must obtain a vote of confidence from each house of parliament -- the Senate and the Chamber of Deputies.

The Five Stars and the League agreed on Conte's name after their respective grassroots supporters approved a so-called "contract" outlining how the two forces plan to govern Italy over the weekend.

The decision follows on a number of false starts and failed consultations, more than two months after Italy's inconclusive March 4 general election that delivered no clear winner, forcing the two top vote-getters into an alliance.

"This is a historic moment," Movement chief Luigi Di Maio told reporters in televised comments after meeting with Mattarella.

Di Maio confirmed minutes later in a blog post that Conte got the nod. "I am particularly proud of this choice," Di Maio's statement said.

"No one has anything to fear," League leader Matteo Salvini said after meeting with the president of the country, in reference to warnings about Italy's possible new euroskeptic government being sounded by the European Union and international observers. "The government we will participate in will respect its commitments, but wants to make Italy grow. Italians first."

Salvini declined to specify who the candidate is, but local media report that the League also backed Conte.

According to press reports, the Five Star-League cabinet will be made up of 18 ministers, with Salvini to enforce his party's anti-immigrant policies as chief of the Interior Ministry and Di Maio heading up a possible joint Labor-Industry Ministry to roll out the Movement's flagship promises of a basic income and other generous welfare spending.

Conte first emerged from relative obscurity days before the general election, when Five Star chief Di Maio introduced him in a televised event as the Movement's candidate for the post of "civil service, de-bureaucratization and meritocracy minister."

In his early 50s, Conte obtained a law degree from Rome's La Sapienza University in 1988 and teaches private law at Florence University.

According to a curriculum vitae published online by the Chamber of Deputies, or Lower House of parliament, Conte sat on a government commission for the reform of the civil law code in 1998, during the center-left administration of Romano Prodi.

"Traditionally, my heart has always beaten to the left," Conte has been quoted as saying in reference to his political leanings.

The academic, who has zero experience in public administration, will lead a coalition seeking billions of euros in tax cuts, additional welfare spending and a roll-back in pension reforms -- expensive measures that according to an editorial by leading Italian economist Carlo Cottarelli on La Stampa newspaper, could increase Italy's public deficit by "110-125 billion euros" (130-147 billion US dollars).

Also on Monday, one of the "top three" international debt rating agencies sounded an alarm. "The coalition policy agreement of Italy's two most populist and eurosceptic parties increases risks to the country's sovereign credit profile, notably through fiscal loosening and potential damage to confidence," Fitch Ratings said in a statement.