Biden, in Rome for pope's inauguration, meets Napolitano

US Vice President Joe Biden traded quips Monday with Italian President Giorgio Napolitano on the eve of a grand mass to inaugurate Pope Francis.

"I didn't realise you'd arrange for a new pope so quickly," Biden joked, prompting Napolitano to reply: "They are quicker than Italian politics."

Italy remains locked in a political stalemate since February 24-25 elections failed to produce a clear winner.

Napolitano, 87, will begin meeting party leaders on Wednesday with a view to forming a government and ending the impasse.

The US vice president, a practising Catholic, said: "I'm delighted to be here for Pope Francis. He shares a vision that all of us share, to reach out to the poor and the dispossessed."

Biden noted that President Barack Obama would have attended Tuesday's mass but was due to begin a visit to Israel on Wednesday.

"The president sends his regards, and the only reason he's not here is he's going to Israel," Biden said.

Napolitano said Italians "strongly hope (for) a real, really effective peace process" in the Middle East.