AKIPRESS.COM - The United States will send around 600 new troops to Iraq to assist local forces in the battle to retake Mosul from Islamic State that is expected later this year, U.S. and Iraqi officials said on Wednesday.

The new deployment is the third such boost in U.S. troop levels in Iraq since April, underscoring the difficulties President Barack Obama has had in extracting the U.S. military from the country, Reuters reported.

Iraqi Prime Minister Haider al-Abadi said in a statement that his government asked for more U.S. military trainers and advisers. Obama called it a "somber decision."

"I've always been very mindful that when I send any of our outstanding men and women in uniform into a war theater, they're taking a risk that they might not come back," Obama said during a town hall event at a military base in Fort Lee, Virginia, televised on CNN.

The new troops will train and advise Iraqi security forces and Kurdish peshmerga forces, primarily in the Mosul fight, but also serve "to protect and expand Iraqi security forces' gains elsewhere in Iraq," U.S. Defense Secretary Ash Carter said.

"We've said all along - whenever we see opportunities to accelerate the campaign, we want to seize them," Carter said.

Though Iraqi forces will be in the combat role, "American forces combating ISIL in Iraq are in harm's way," Carter said, using an acronym for Islamic State.

Some of the 615 new service members will be based at Qayara air base, about 40 miles (60 km) from Mosul, Carter said. Iraqi forces recaptured the base from Islamic State militants in July and have been building it into a logistics hub to support their offensive into the northern city.

Other U.S. troops will go to Ain al Asad air base in western Iraq, where hundreds of U.S. personnel have been training Iraqi army forces.