The U.S. mission in Iraq has stalled at one of five coalition training sites because the central government has not been sending new recruits, according to defense officials. 
 
 Baghdad has not identified or sent any new recruits to the Al Asad air base in western Iraq for as many as four to six weeks, defense officials said Monday. 
 
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 The U.S. is currently training 2,601 Iraqi forces, but none of them are at Al Asad, officials said. 
 
 "Al Asad has zero. And Al Asad has had zero now for some time," said one defense official on background. 
 
 The stall has prompted U.S. officials, including President Obama, to urge the Iraqi government to speed up its recruitment efforts. The training is a key component of the U.S.-led military effort against the Islamic State in Syria and Iraq (ISIS). 
 
 "One of the things that we're still seeing is, in Iraq, places where we've got more training capacity than we have recruits," Obama said Monday after a discussion with Iraqi Prime Minister Haider al-Abadi. 
 
 "Part of my discussion with Prime Minister Abadi was how do we make sure that we get more recruits in. A big part of the answer there is our outreach to Sunni tribes. We've seen Sunni tribes who are not only willing and prepared to fight ISIL, but have been successful at rebuffing ISIL. But it has not been happening as fast as it needs to," he said, using an alternate name for the group. 
 
 The Al Asad air base is one of the primary sites for training Sunni tribal fighters, which the U.S. has left entirely up to the Iraqi forces out of deference to Baghdad. 
 
 At one point earlier this year, there were several hundred U.S. troops — including about 300 Marines — training other Iraqi forces at the base. It is unclear how many are there today. 
 
 The training and equipping of Sunni tribal fighters became more urgent after the fall of Ramadi last month, which is the capital of Anbar Province — referred to as the "Sunni heartland." 
 
 Sunni forces who were defending the city said they had not received any training or equipment from the central government, which is dominated by Shiites. 
 
 The U.S. has resisted directly training or equipping Sunni forces out of concern it could undermine Baghdad, which views the Sunni population with mistrust, and worsen sectarian tensions. 
 
 Defense officials believe the training has stopped for two main reasons: the difficulty of bringing forces to the base, and the government of Iraq being "still not completely unified." 
 
 "They still haven't gotten over many of their sectarian divides, so that is creating some of the problems as well," the defense official said. 
 
 The U.S.-led coalition has so far trained about 8,920 at the five training sites in Iraq. Those include one located near Baghdad, and others in Erbil, Taji, Al Asad and Besmaya. 
 
 There are approximately 910 trainees at the site near Baghdad, which is training Iraqi special operations forces, 800 trainees at the Erbil training site, 255 trainees at Besmaya, and 630 trainees at Taji. ||||| Alistair Baskey, a National Security Council spokesman, said that the administration hoped to accelerate the training and equipping of Iraqi security forces, and that “those options include sending additional trainers.” The United States now has about 3,000 troops, including trainers and advisers, in Iraq. But the steps envisioned by the White House are likely to be called half-measures by critics because they do not call for an expansion of the role of American troops, such as the use of spotters to call in airstrikes. 
 
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 There has long been debate within the administration about what the first steps in the campaign should be. 
 
 Led by Gen. Lloyd J. Austin III, the Central Command has long emphasized the need to strike a blow against the Islamic State by recapturing Mosul, Iraq’s second-largest city, which was taken by the group in June 2014. Mosul is the capital of Nineveh Province in northern Iraq and was the site of a sermon that Abu Bakr al-Baghdadi, the leader of the Islamic State, defiantly delivered in July. The Baiji refinery, a major oil complex, is on a main road to Mosul. 
 
 While General Austin was looking north, State Department officials have long highlighted the strategic importance of Anbar Province in western Iraq. 
 
 Anbar is home to many of Iraq’s Sunni tribes, whose support American officials hope to enlist in the struggle against the Islamic State. Ramadi, the provincial capital of Anbar, is less than 70 miles from Baghdad, and the province borders Saudi Arabia and Jordan, two important members of the coalition against the Islamic State. 
 
 The differing perspectives within the administration came to the fore in April when Gen. Martin E. Dempsey, the chairman of the Joint Chiefs of Staff, asserted that Ramadi was not central to the future of Iraq. 
 
 The Islamic State’s capture of Ramadi last month also punctured the administration’s narrative that the group was on the defensive. 
 
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 Suddenly, it appeared that the Islamic State, not the American-led coalition, was on the march. Prime Minister Haider al-Abadi of Iraq scrambled to assemble a plan to regain the city. 
 
 The Islamic State now controls two provincial capitals, as well as the city of Falluja. With the help of American air power, the Iraqis have retaken Tikrit, northwest of Baghdad, but so many buildings there are still rigged with explosives that many of its residents have been unable to return. 
 
 To assemble a force to retake Ramadi, the number of Iraqi tribal fighters in Anbar who are trained and equipped is expected to be increased from about 5,500 to as many as 10,000. 
 
 More than 3,000 new Iraqi soldiers are to be recruited to fill the ranks of the 7th Iraqi Army division in Anbar and the 8th Iraqi Army division, which is in Habbaniyah, where the Iraqi military operations center for the province is also based. 
 
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 But to the frustration of critics like Senator John McCain, Republican of Arizona, who say that the United States is losing the initiative to the Islamic State, the Obama administration has yet to approve the use of American spotters on the battlefield to call in airstrikes in and around Ramadi. Nor has it approved the use of Apache helicopter gunships to help Iraqi troops retake the city. 
 
 General Dempsey alluded to the plan to expand the military footprint in Iraq during a visit to Israel on Tuesday, saying that he had asked war commanders to look into expanding the number of training sites for Iraqi forces. Speaking to a small group of reporters, General Dempsey said a decision had not been made on whether that would make additional American troops necessary. 
 
 “T.B.D. — to be determined,” General Dempsey said. A Defense Department official said afterward that a decision to increase American troops in Iraq would most likely require only a “modest” number of additional trainers. 
 
 The United States is not the only country that is expanding its effort. 
 
 Britain’s prime minister, David Cameron, said this week that his country would send up to 125 additional troops to train Iraqi forces, including in how to clear improvised bombs. 
 
 Italy is also expected to play an important role in training the Iraqi police. ||||| Following ISIS’s taking of Ramadi in Iraq, the White House will mobilize about 500 more military trainers to bolster its strategy to defeat ISIS and train Iraqi troops. Photo: Getty Images 
 
 President Barack Obama is poised to send hundreds more American military advisers to a new base in a strategic Iraqi region to help devise a counterattack against marauding Islamic State militants, U.S. officials said Tuesday, a shift that underscores American concern over recent battlefield losses. 
 
 The additional troops—expected to be about 500—are intended to help Iraqi forces prepare for the looming fight to break the extremists’ hold on Anbar province, which has long served as a command center for anti-American insurgents...
– Instead of trying to help Iraqi forces recapture the city ISIS seized a year ago, the US has decided to focus on helping them capture the city militants seized less than a month ago. Ramadi is the capital of Anbar province, and the White House is expected to approve a Pentagon plan to establish a new base in the province and send up to 500 more military trainers there, the Wall Street Journal reports. American officials say there had been some debate about how much of a priority recapturing Mosul, the country's second-largest city, would be, but the recent fall of Ramadi settled the question; now Mosul may have to wait until 2016, reports the New York Times. Defense Secretary Ash Carter blamed the fall of Ramadi on Iraqi forces' lack of will to fight. Critics say the proposed modest expansion of the US role is nowhere near what's required to defeat ISIS, the Journal reports. "One has to wonder whether this president just wants to wait out the next year and a half and basically do nothing to stop this genocide, bloodletting, horrible things that are happening throughout the Middle East," Sen. John McCain told fellow senators Monday. The new troops will bring the number of US advisers and trainers in Iraq to around 3,600, but there's a shortage of people for them to train in at least one site, the Hill reports. Defense officials say it has been more than four weeks since the Baghdad government sent any recruits to Al Asad air base, although 2,601 Iraqis are being trained elsewhere.