BAGHDAD, Iraq: Iraq is facing two major deadlines at the end of September: the end of the decades-long U.S. military presence and a government demand for non-state armed groups to give up their weapons.

The U.S. military withdrawal is already under way. U.S. officials said the hundreds of American troops still in northern Iraq are expected to leave by September 30.

The Iraqi government has linked the U.S. withdrawal to its demand that militias disarm. However, most powerful armed groups have made clear that they have no plans to surrender their weapons.

This has raised questions about what Iraq's security situation will look like after the US troops leave.

Iran-backed Iraqi militias have attacked U.S.-linked targets in Iraq and elsewhere since the United States and Israel attacked Iran on February 28. The militias have also coordinated with Yemen's Houthi rebels in attacks on Saudi Arabia.

With the U.S.-Iran war continuing, Iran is unlikely to give up its influence in neighboring Iraq. U.S. officials remain concerned that Iraqi militias could continue attacks across the region, but Washington does not appear willing to delay its troop withdrawal.

U.S. forces invaded Iraq in 2003 and overthrew Saddam Hussein. They left in 2011, but returned three years later after Iraqi authorities asked for help fighting Islamic State, which had captured large parts of the country.

Islamic State has since been reduced to scattered sleeper cells. Iran-backed militias, along with the U.S.-led coalition, played a major role in defeating the group. In 2024, Washington and Baghdad agreed to gradually end the U.S.-led military mission.

Most U.S. troops left Iraqi bases last year, but several hundred remained in the semi-autonomous Kurdish region in the north. Those bases have repeatedly come under attack since the U.S. and Israel began their war against Iran.

A U.S. military official said the withdrawal would be completed by September 30. Most of the remaining troops in northern Iraq are expected to move to Jordan and other countries in the region. Military equipment, including air defense systems, will also be removed.

The official said the United States could later negotiate a normal bilateral security cooperation agreement with Baghdad, although its exact form remains unclear.

The U.S. official also said the counterterrorism base in Erbil had become less important as the Islamic State threat declined. Northern Iraq was generally not used as an offensive base during the war with Iran, but U.S. forces there were frequently targeted by Iran and Iran-backed militias. Their withdrawal is therefore expected to reduce the risk to American personnel.

However, Washington remains concerned about the militias' ability to attack targets in Saudi Arabia, Jordan and Israel. It is also concerned about the presence of Houthi fighters in Iraq.

The United States has previously attacked militia positions in Iraq in response to attacks and has imposed sanctions on some groups. More sanctions could follow.

The Iraqi government has not been clear about whether September 30 is a firm deadline for disarmament or simply the beginning of negotiations.

Iraqi analyst Sajad Jiyad said the major militias were unlikely to give up their weapons by that date. "There will be no disarming of any groups by the 30th of September," he said at a recent panel organized by the Atlantic Council.

A few smaller militias have agreed to hand over their weapons. But powerful groups such as Kataib Hezbollah, Harakat al-Nujaba and Kataib Sayyid al-Shuhada have rejected disarmament or demanded conditions that the Iraqi government is unlikely to accept soon.

Their demands include placing Kurdish peshmerga forces under the control of the central government and removing Iranian Kurdish opposition groups and the Kurdistan Workers' Party, or PKK, from northern Iraq.