They are due to meet President Sergio Matterella at the presidential palace on Monday evening to formally present their choice.
After a week of haggling, M5S leader Luigi Di Maio and League leader Matteo Salvini closed a coalition deal and announced a joint programme which turns its back on austerity measures.
Both Di Maio and Salvini dreamed of running the first anti-establishment government within an EU-founding nation, but a clash of egos and lack of majority in parliament forced them to opt for a third candidate. Media reports say the pair will, however, lay claim to their top ministerial picks: interior minister for the nationalist Salvini and minister of economic development for Di Maio.
"We have agreed on the leader and ministers of government and we hope that no one will veto a choice that represents the will of the majority of Italians," Salvini said on Sunday.
Rumours are also swirling around the nomination for premier with the media betting on a handful of candidates. Giuseppe Conte, 54, a lawyer who teaches law in Florence and Rome is among the rumoured top picks. Though little known in Italy, he has an impressive CV with teaching stints at Yale, Cambridge and Sorbonne.
Andrea Roventini, a 41-year-old economist teaching at the university of Pisa has also been touted as another contender as well as Paolo Savona, 81. Minister for industry between 1993-94, Savona was staunchly opposed to the signing of the Maastricht Treaty which, in the M5S-League programme, is cited as the moment the EU went off track.
M5S leader Luigi Di Maio and League leader Matteo Salvini. Photo: Tiziana Fabi/AFP
Never afraid of a long shot, former premier Silvio Berlusconi, who is upset with his right-wing ally Salvini, has also offered himself up as future premier.
Following a recent court ruling, the ageing billionaire is once again legally allowed to hold public office and has expressed his discontent with the coalition programme, especially the strict measures against conflict of interests in parliament which he sees as directly targeting his media empire.
"Salvini never spoke on behalf of the right-wing coalition, but only on his own behalf and on behalf of the League," he said on Friday evening. Berlusconi said his Forza Italia party would present a "reasonable and scrutinizing opposition" to the new government and suggested he could run the government if Salvini decided to ditch M5S.
Mattarella must agree to the parties' nominee before they can seek parliament's approval for their nascent government. The president will also examine the new M5S-League joint programme, overwhelmingly approved over the weekend in a public non-binding vote.
The 58-page programme does not mention a unilateral exit from the eurozone unlike previous versions leaked to the media, but it rejects post-financial crisis austerity policies and features hardline immigration and security proposals.
The document's costly financial measures and eurosceptic tone have got the financial markets worried. The Milan Stock Exchange opened down by nearly two percent Monday, while the spread – the difference between the Italian and German ten-year borrowing rates – has gained 40 points in less than a week, increasing to 170 points.
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