ROME (Reuters) - Italy should have a “plan B” to quit the euro zone with a referendum if economic conditions dictate, the founder of the co-ruling 5-Star Movement said, sending ripples through financial markets.

FILE PHOTO: 5-Star Movement founder Beppe Grillo speaks during the finally rally ahead of the March 4 elections in downtown Rome, Italy, March 2, 2018. REUTERS/Tony Gentile

The anti-establishment movement’s founder Beppe Grillo holds no post in the coalition where 5-Star governs with the League. But his remarks may fuel new doubts over Italy’s intention to maintain the single currency.

“You must have a plan B,” Grillo said in an interview on Friday with Gzero Media, a subsidiary of risk analysis firm Eurasia Group.

His comments came as Italy’s new anti-establishment government designated a eurosceptic as president of the national public broadcaster RAI, whose TV channels are the most popular among Italians.

Grillo said the country had not devised any contingency plan yet, and Italians should vote in a referendum to see if a majority wanted to quit the currency.

Prime Minister Giuseppe Conte and Economy Minister Giovanni Tria have both said the government has no intention of leading Italy out of the euro.

However, Italian shares .FTMIB erased gains on Friday and two-year bond yields briefly hit a two-week high. Traders cited Grillo's comments, which echoed the controversial position of Italian minister for European affairs, Paolo Savona.

Meanwhile, the government designated journalist Marcello Foa as president of RAI. In his blog, Foa has criticised European Central Bank’s president Mario Draghi for saying that the euro is irreversible.

“Only the people can decide on whether a currency is irreversible or not,” he wrote in February.

“I am sure that Germany and France have their plan B,” Grillo said in his interview, citing the two largest economies of the euro zone. “I am not saying that we should quit the euro without discussion, but we should let the Italian people decide with a referendum.”

Grillo remains influential but plays little role in the day-to-day management of the 5-Star Movement.

Savona was forced by Italian President Sergio Mattarella to renounce the post of finance minister because of his statements on the need for such a contingency plan.

In a post on Facebook, Foa expressed “disgust” at Mattarella’s doubts over Savona.

His appointment as RAI president will need to be confirmed by parliament where the League and 5-Star have a comfortable majority.

Separately on Friday, the Italian government appointed experienced manager Fabrizio Salini in the more powerful position of RAI chief executive officer.