The shock manifesto, entitled Government for Change, reveals plans for Italy to leave the single currency, calls for sanctions against Russia to be scrapped and reveals plans to ask the European Central Bank to write off the country’s £250bn debt.
The 39-page document emerged as Italy’s political deadlock looks set to continue with Forza Italia leader Silvio Berlusconi refusing to stand aside to let his anti-EU election allies Lega form a eurosceptic government with anti-establishment 5Star.
President Sergio Mattarella has demanded action after a third inconclusive round of coalition talks and warned party leaders to find an agreement, accept a “neutral government” or face new elections.
The joint Government for Change programme appears to show plenty of common ground between Lega and 5SM and is signed by their respective leaders Matteo Salvini and Luigi Di Maio.
The leaked report demands radical change in Italy’s relationship wth Brussels with "a need to revise EU treaties" and to "re-discuss the Italian contribution to the EU in view of the 2020 plan".
On the European front, while confirming the loyalty to NATO with the US, a "privileged ally", it establishes "the opening to Russia, to be perceived not as a threat, but as an economic and commercial partner”.
During the election campaign Lega promised "the immediate withdrawal of sanctions imposed on Russia" and the rehabilitation of Moscow as a "strategic interlocutor" in crisis areas such as Syria, Libya and Yemen.
On public finance, Mr Salvini and Mr Di Maio resolve to ask ECB chief Mario Draghi to cancel the £250 billion government bonds it owed.
The document states the "system of European economic governance - so-called Stability and Growth Pact - based on the dominance of the market and the respect of the stringent economic and social constraints must be re-thought with other European partners.
And the report demands a review of monetary policy and calls for a return to the pre-Maastricht approach in which EU members were motivated by a genuine intent of “peace, brotherhood cooperation and solidarity".
The parties have issued a joint statement insisting the document was an old draft that contained many proposals that had been ammended.
They said: "The government contract is an old version that has already been extensively modified during the last two meetings.
“Many of the contents have radically changed: the parties have already decided not to question the single currency, so the published version is not faithful to the current one".
Mr Di Maio said: "The draft changes so quickly that I don’t read the updates anymore. The published one is anachronistic and has changed".
Maurizio Martina, secretary of the rival Democratic Party, condemned the document.
He said: “Between hypotheses of abandoning the Euro and dangerous parallel committees, Lega and Cinque Stelle are playing with the credibility of the country.
"Italy does not deserve all this.”