Italian centre-left leader Pier Luigi Bersani met his centre-right rival Silvio Berlusconi today to discuss the election for the next president of the Republic, offering hope of a breakthrough in the deadlock left by elections in February.

"It was a good meeting but we're at the beginning," Enrico Letta, deputy leader of Bersani's Democratic Party (PD), told reporters in parliament.

He said the meeting had focused only on the issue of the next president, not on any possible deal to form a government, which has so far proved impossible for the deeply divided parties to secure more than 40 days after the election.

Letta said there would be further meetings in the next few days with Berlusconi's People of Freedom (PDL) and other parties but said no names were discussed at Tuesday's meeting, intended to prepare the way for the start of the presidential election process on April 18.

The election of the next president, to succeed Giorgio Napolitano whose term ends on May 15, is the next big test for the parliament, which is split between the two traditional centre-right and centre-left blocs as well as the anti-establishment 5-Star Movement.

It is unclear how far any accord over the presidential election will clear the way to a deal that would allow a government to take office but the tone struck following the meeting was much more cordial than it has been in recent days.

"It was useful to get clarity on the criteria we need first to agree on a range of names, then on a person who can unite the country," Letta said.

"In a moment of great division we feel a strong need to give a signal of unity to the country. That's why we want to try to find unity around a name we can both support," he said.

In a separate statement, PDL secretary Angelino Alfano said the next president would have to be acceptable to his party although he did not repeat Berlusconi's previous demands that the centre-right should choose the head of state.

"The president must represent national unity and therefore cannot be, or even appear to be, hostile to a significant part of the Italian people," he said.

No clear favourite has emerged although several names have been floated including former prime ministers Romano Prodi and Giuliano Amato and former European Commissioner Emma Bonino.

"WE HAVEN'T FORGOTTEN"

The vote for the next president will be vital because with his mandate about to expire, Napolitano no longer has the power to dissolve parliament and call new elections and it will be up to his successor to find a way out of the deadlock.

Bersani, who won a majority in the lower house but fell short of the Senate majority which would have allowed him to govern, has so far refused Berlusconi's demands for a "grand coalition" between the two rival forces.

The other main force, the 5-Star Movement led by ex-comic Beppe Grillo, has refused any alliance with either of the big parties it blames for Italy's deep social and economic crisis.

In an interview with RAI state television, Bersani stuck to his rejection of Berlusconi's demands to form a coalition, saying the centre-right leader had shown during the technocrat government of Mario Monti that he could not be trusted.

"When I meet him, I will say, 'We haven't forgotten. We know you even if you try to disguise yourself'," he said.

"We're trustworthy and we look for trustworthiness in others, if there are proposals, we'll see. Only they shouldn't come with proposals for a 'governissimo' because that's not possible. If they've got other ideas, we can talk about it."

Bersani has so far stuck to his hard line on Berlusconi despite increasing calls from senior figures in sections of his party for a dialogue with the centre-right to avoid a potentially destabilising return to the polls.

He wants to present a limited set of proposals to parliament and seek a wider accord among the parties for a broad series of institutional reforms, including changes to the widely criticised electoral law which led to the stalemate.

Berlusconi has demanded that the centre-right be allowed to choose the next head of state as the price of its support to a government led by the centre-left. He says the only alternative is new elections at the earliest date possible in June or July.