Opposition politicians in Italy called for an explanation from Matteo Salvini, the deputy prime minister, about reports that his party secretly sought financing from Moscow.

The hard-Right League, led by Mr Salvini, was in talks with Russian businessmen close to the Kremlin to secure funding through a petrolium export deal, according to Espresso, an Italian news magazine.

Under the arrangement, millions of euros’ worth of diesel was to be sold to an Italian company by a Russian firm “close to the Kremlin”, with the profits to be diverted to the League, the weekly claimed.

But the magazine conceded that it did not know whether the deal, allegedly intended to fund the League’s political campaign ahead of the European Parliament elections in May, was ever concluded.

Asked about the claims, a spokesman for The League told The Telegraph: “We don’t comment on science fiction and fantasies.”

The report prompted opposition MPs to demand an explanation from the party, which governs Italy in coalition with the anti-establishment Five Star Movement.

“Russia is financing the League? The worrying report by Espresso needs to be immediately clarified by the government,” the centre-Left Democratic Party said in a statement.

“It is claimed that a Russian energy company sold supplies of petrol to an Italian firm with the objective of financing Salvini’s Europe campaign.