The United States and its allies have begun rushing antitank weapons, other arms and ammunition to Kurdish fighters battling heavily armed Islamic militants in northern Iraq, another step in America's rapidly deepening reengagement in the country.
President Obama also increased pressure Monday on Iraqi Prime Minister Nouri Maliki, whom the U.S. accuses of alienating Sunni Arabs and pushing them into the militants' camp, to step aside and make room for a new government.
The two-pronged U.S. effort is aimed at halting Iraq's slide toward disintegration less than three years after the last U.S. combat troops left. Maliki has refused to quit, and the volatile political standoff has undermined the government's ability to confront radical Islamic State fighters who have overrun much of western and northern Iraq.
Speaking to reporters Monday from his vacation compound on Martha's Vineyard, Obama said he and Vice President Joe Biden had telephoned and offered full U.S. support to Haider Abadi, the deputy speaker of the Iraqi parliament, who was named by President Fouad Massoum early Monday to succeed Maliki.
Calling the development "a promising step forward," Obama said he had urged Abadi to form a Cabinet as quickly as possible, "one that's inclusive of all Iraqis and one that represents all Iraqis." Under Iraqi law, Abadi has 30 days to put together a government.
Obama did not mention Maliki, whose supporters say is being made a scapegoat for Iraq's myriad problems. They accuse foreign powers of conspiring to oust him.
Over the weekend, U.S. officials released several statements supporting the Iraqi president, and diplomats in Washington and Baghdad encouraged Iraqi politicians to reach agreement on an alternative to Maliki. Abadi, like Maliki a member of Iraq's Shiite Muslim majority, spent years in exile in Britain when Saddam Hussein ruled Iraq.
Unless Maliki cedes power, "the situation could spiral in a very uncertain and dangerous direction," Ramzy Mardini, an analyst with the Atlantic Council, a nonpartisan think tank, said in an email. On Sunday, Maliki had ordered tanks and troops into the streets of Baghdad as a show of force.
The showdown in Baghdad has complicated Obama's decision last week to authorize airstrikes in northern Iraq against forces of the Islamic State, a breakaway Al Qaeda faction. Those strikes continued Monday as warplanes attacked four checkpoints manned by the militants near Mt. Sinjar, where the extremists have threatened to kill thousands of displaced Yazidis they say are religious apostates.
The Pentagon said the attacks destroyed an armored personnel carrier, four trucks and a U.S.-made Humvee.
Four U.S. military cargo planes made a fifth airdrop of food and water to those trapped on Mt. Sinjar.
The insurgents have captured vast stores of arms, ammunition and equipment, including armored Humvees and personnel carriers, from fleeing Iraqi army forces in recent months. Outgunned Kurdish commanders say their forces' light weapons cannot penetrate the American-made armored vehicles.
The CIA has secretly sent small shipments of arms to the Kurds in recent days. The Pentagon is preparing to take over and increase the effort, drawing on its stockpiles and those of allies in the region, officials said.
Lt. Gen. William Mayville, director of operations for the Pentagon's Joint Staff, said the U.S. intended to provide "longer-range weapons" that can destroy the U.S.-made vehicles and other heavy equipment.
The needs of the Kurdish forces are "pretty substantial," Mayville said at a Pentagon news briefing.
The White House decided to switch course after Kurdish troops outside Irbil, the regional capital, retreated from a militant offensive last week when they ran low on ammunition and resupply efforts from Iraqi and Kurdish stockpiles faltered, officials said.
The decision to give U.S. weapons to the Kurds is an about-face for Washington, which has long had a policy of funneling military aid to Kurdish troops, known as peshmerga, only through the government in Baghdad.
A State Department spokeswoman, Marie Harf, declined to say whether the administration had Baghdad's consent to send arms directly to the Kurds, who control an oil-rich semiautonomous region in Iraq.
"The Kurds need additional arms," she said. "We are providing those and working to provide" more.
A senior administration official, speaking on condition of anonymity to discuss internal deliberations, said arms were being delivered directly to the Kurds because of the urgency of the battle against the militants.
A Kurdish leader, who spoke on condition of anonymity to discuss the negotiations, said the Kurdish militias already had begun receiving heavier weapons from U.S. stockpiles.
"This … is a war of firepower," the leader said in a telephone interview from Irbil. "Really there is no match between the weapons they have acquired and our weapons."
Islamic State fighters are "very, very well organized," he said. "They are not just amateurs and suicide bombers. They have strategic thinking and movement and military planning and so on.... The balance of forces on the ground has changed, and fast."
Kurdish forces have requested long-range anti-armor mortars, shoulder-fired rockets and Russian-designed 14.5-millimeter and 12.5-millimeter heavy machine guns.
Like many militias, the peshmerga have long relied on AK-47s and other weapons of Russian origin. The CIA keeps a stockpile of such weapons, which was used to speed supplies to Kurds last week.
The Pentagon is being brought in to greatly expand deliveries of arms and ammunition, a U.S. official said.
Because the Pentagon does not stockpile Russian-designed weapons, the U.S. is enlisting other countries in the region that can supply them to the Kurds. The U.S. officials would not say which countries were being asked to join the effort.
The U.S. and allies in the region have long been wary of arming the Kurds, fearing it would strengthen their drive for independence. Some predominantly Sunni Arab countries also are concerned about sending arms that will be used against fellow Sunni Muslims, even if they are militants in the Islamic State.
Privately, some U.S. officials said the decision to arm the Kurds illustrated the dire security situation in northern Iraq and the lack of faith in the Iraqi army, whose troops retreated by the tens of thousands.
Officials acknowledged that U.S. airstrikes are not likely to achieve lasting gains against the militants unless Kurdish and Iraqi ground troops regain their footing.
Although the U.S. attacks on militants that began Friday may have blunted their push toward Irbil, Mayville said, "I in no way want to suggest that we have effectively contained or that we are somehow breaking the momentum" of the militant fighters.
Times staff writers Patrick J. McDonnell in Irbil, Kathleen Hennessey in Chilmark, Mass., and David Lauter in Washington contributed to this report.