A coalition of Silvio Berlusconi’s forces and centre-left rivals forged a new Italian government on Saturday, an unusual alliance that broke a two-month deadlock following inconclusive elections in the recession-mired country.

The daunting achievement was pulled off by Enrico Letta, a centre-left leader who will be sworn in as Premier along with the new Cabinet on Sunday at the presidential Quirinal Palace.

A moderate with a reputation as a political bridge-builder, Mr. Letta (46) is also the nephew of former Premier Silvio Berlusconi’s longtime adviser, Gianni Letta, a relationship seen as smoothing over often nasty interaction between the two main coalition partners.

Serving as Deputy Premier and Interior Minister will be Mr. Berlusconi’s top political aide, Angelino Alfano. The creation of the coalition capped the latest political comeback for Mr. Berlusconi, who was forced to resign in 2011 as Italy slid deeper in to the eurozone’s sovereign debt crisis.

Mr. Berlusconi, a fervent anti-Communist, views Italy’s left as a personal nemesis, and Mr. Letta’s Democratic Party has some of its roots in what was the West’s largest Communist Party.

Mr. Letta, expressed “sober satisfaction over the team we put together and its willingness” to form a coalition.

President Giorgio Napolitano, who tasked Mr. Letta with creating a government out of bitter rivals, called upon the coalition partners to work “in a spirit of absolute, indispensable cohesion” as they work for sorely needed political and economic reforms.

“I hope there is maximum cohesion,” said Mr. Napolitano, sounding almost breathless as he expressed confidence the rivals could work together for the good of the country.

Mr. Napolitano said: “It was and is the only possible government,” adding there was no room for “delay, in our country’s and Europe’s interests”.

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