ROME, Italy (Reuters) -- Italy's president accepted Prime Minister Romano Prodi's resignation on Wednesday following the government's defeat in a Senate vote on foreign policy.
Prodi, in power for nine months, went to the Quirinale (president's palace) after a cabinet crisis meeting.
President Giorgio Napolitano, the supreme arbiter of Italian politics, will hold talks with party leaders on Thursday to discuss the way forward.
Divided over the Afghan war and ties with the U.S. military, Prodi's center-left government was unable to secure enough votes for a motion backing Rome's foreign policy.
There was no constitutional requirement for Prodi to step down. But Foreign Minister Massimo D'Alema had said before the Senate vote that the government should resign if it did not command majority support on foreign policy.
Napolitano's options include dissolving parliament and calling an election. He could also ask Prodi to form a new government or broker the formation of a different government, possibly involving technocrats.
The defeat was the most serious setback for Prodi's coalition government, also deeply divided over a host of domestic issues ranging from the budget, pension reform and a bill giving legal recognition to gay and unwed couples.
The parliamentary motion, a broadly worded declaration of support for foreign policy, received 158 votes in favor, below the necessary majority of 160 votes, and was followed by opposition calls for the government to quit.
Prodi's coalition had only a one-seat majority in the Senate but in the past had managed to muster support by calling confidence votes.
Renato Schifani, Senate leader of the biggest opposition party, Forza Italia, held up a copy of Wednesday's La Stampa newspaper which had quoted D'Alema's warning to coalition pacifists who oppose Italy's military presence in Afghanistan.
"I have in my hand one of the most important newspapers in the country with a declaration by Foreign Minister D'Alema: 'Resignation if we have no majority'," Schifani said to cheers from allies.
"There is no majority any more ... There is no Prodi government any more. The Prodi government has fallen in this chamber."
Earlier a political source in the Catholics-to-communists ruling coalition said he expected Prodi to survive the ordeal but said D'Alema, who is also deputy prime minister, would likely resign as foreign minister.
Beyond Afghanistan, where Italy has 1,900 troops on a NATO-led mission, one of the most divisive issues has been a plan to expand a U.S. military base in northern Italy.
Protests against the plan drew tens of thousands of Italians, including some senior coalition members, last weekend.
D'Alema said the government was compelled to allow the base expansion. "Revoking the authorization would have been a hostile act on our part against the United States," he said.
But one leftist senator announced he would resign rather than vote for D'Alema's motion. "I am against the war in Afghanistan and against the U.S. base in Vicenza," said Franco Turigliatto, with the Communist Refoundation party.
