Italy (search), one of Washington's most stalwart allies in Iraq (search), announced it could begin pulling its troops out in September, an acknowledgment by Premier Silvio Berlusconi (search) that Italian public opinion is heavily against the war.

The announcement Tuesday by the conservative leader was the most high-profile crack in what the U.S. administration has boasted in the past was a solid alliance. The Netherlands is ending its mission this month, and Poland plans to withdraw some troops in July.

"Starting with the month of September, we would like to proceed with a gradual reduction of our soldiers," on condition that Iraq could provide "acceptable" security, Berlusconi said.

Word from one of President Bush's closest allies that some of Italy's 3,300 troops would start leaving Iraq within year's end came as the Italian leader confirmed he is running to keep the premiership in general elections in spring 2006.

Italy's center-left opposition, which was strongly opposed to war in Iraq, on Wednesday welcomed Berlusconi's announcement.

"About time, better late than never," said opposition leader Romano Prodi, a former premier and former EU commission president who is expected to be Berlusconi's opponent in political elections next year.

"It's the logical consequence of a wrong decision," Prodi was quoted as saying in daily La Repubblica on Wednesday. "This long-awaited news confirms our stance."

Hours earlier, Italy suffered its latest casualty in Iraq, the 21st military member killed since it sent in some 3,000 troops after the ouster of Saddam Hussein. The nation lost 19 Italians, most of them military members, in the November 2003 suicide truck bombing of Italian paramilitary police barracks in Nasiriyah, southern Iraq.

Italy is also still grappling with the shock and outrage over the killing of an Italian intelligence agent earlier this month as he was accompanying a just-freed Italian hostage to Baghdad airport. U.S. soldiers patrolling near the airport mistakenly fired on the car in which the two were traveling.

The premier said he had spoken about the situation with British Prime Minister Tony Blair, another of Bush's closest allies in Iraq.

As the situation stands now, the reduction in the number of Italian forces will start "even before the year's end, in agreement with our allies," the Italian added.

Italy's defense minister had previously said coalition troops in Iraq could be cut gradually after Iraq's elections in January if Iraq could provide its own security, but he didn't specify a timetable.

Italian leaders have demanded U.S. authorities conduct a transparent investigation of the shooting death of military intelligence agent Nicola Calipari on March 4 near Baghdad airport.

"Bush knows he can't disappoint his faithful ally" about the probe, said Berlusconi, who previously tried to get political mileage of his friendship with the American leader.

In Washington, White House spokesman Scott McClellan said, "We certainly appreciate the contributions of the Italians" and said he didn't see a link between the Italian troop withdrawal announcement and Calipari's killing. The former hostage, an Italian journalist, was wounded in the same shooting.

After the shooting incident, Berlusconi's government had made it clear it wasn't yanking its contingent from Iraq.

About the same time Berlusconi was announcing the September date, the Chamber of Deputies was approving extended financing for the nation's military mission in Iraq.