Italy’s Five Star Movement, which has always pledged zero tolerance for corruption, was itself accused of graft on Tuesday, just three weeks before the country’s general election.

The anti-establishment, Eurosceptic Five Star is Italy’s single most popular party, with polls indicating it will win around 28 per cent of the vote, but the corruption scandal could harm its image and erode support.

The party, which was founded by mercurial standup comedian Beppe Grillo nearly a decade ago, believes Italian politicians are over-paid and requires its MPs to donate around half of their monthly salaries to a fund which helps small businesses.

But an investigation by a satirical television programme called Le Iene, or The Hyenas, found that some Five Star MPs had secretly baulked at the requirement.

Instead, they drew up bank orders for the money to leave their accounts, ensuring that they had receipts to show party bosses, but then cancelled them almost immediately.

An unknown number of MPs had failed to reimburse up to €1.4 million, the Italian press reported.

The scandal has already claimed three scalps. On Sunday, Andrea Cecconi and Carlo Martelli, both candidates in the March 4 election, were forced to step down after being accused of failing to reimburse around €100,000.