ROME (Reuters) - Italy's anti-establishment party, 5-Star Movement, said it was willing to drop its opposition to working with Prime Minister Matteo Renzi over electoral reforms if its own proposals are considered.
The 5-Star Movement (M5S), led by former comic Beppe Grillo, had rebuffed repeated calls to work with other parties to reach a broad-based agreement on overhauling Italy's widely criticized electoral system.
However, in a message posted on Grillo's blog, it said the situation had changed since Renzi's success in last month's European parliamentary elections, in which his center-left Democratic Party won a record 40.8 percent of the vote.
The result had given Renzi, appointed prime minister following a party coup in February which deposed his predecessor Enrico Letta, a democratic legitimacy which he previously lacked, it said.
Renzi cautiously welcomed 5-Star's change of stance and said there was no time to waste.
"Now everyone wants to do reforms, before nobody was interested. This is positive, now we have to all sit around a table, this is the week when things have to be decided," he said at a business conference in the northern Veneto region.
M5S had hoped at the European ballot to repeat its barn-storming success at its first ever parliamentary elections last year when it won 25 percent of the vote, but it managed only 21 percent.
"We were convinced we could bring down the government at the European vote, but ... this was not possible and now it seems this administration will have a much longer life," M5S official Luigi di Maio said in a news conference streamed live to Grillo's blog.
The offer, described as a "Copernican revolution" by Il Fatto Quotidiano, an independent daily which has often been sympathetic to Grillo's movement, represents a major turnaround for the party and underlines the extent to which Renzi's position has been strengthened by last month's election result.
Reforming the electoral system, widely blamed for both alienating voters and creating political deadlock, has been a key issue for Renzi, who struck a deal with former Prime Minister Silvio Berlusconi on the issue earlier this year.
M5S said it was ready to open discussions on the basis of its own proposals, which it set out in an open letter to Renzi, who has so far succeeded in implementing little of an ambitious agenda of reforms.
Dubbed "Democratellum", 5-Star's proposal is the latest in a string of Latin-sounding names for voting systems to follow the "Italicum" blueprint agreed between Renzi and Berlusconi. The proposed system is based on a model of proportional representation.
"This is not a pure proportional system but rather one that allows a party that gets around 40 percent of the vote to have more than 50 percent of the seats (in Parliament)," M5S said in the letter.
Reporting By James Mackenzie, Isla Binnie and Gavin Jones; Editing by Susan Fenton