Kurdish pesh merga fighters hold a position on the front line near Irbil in northern Iraq. (Jm Lopez/AFP/Getty Images)

Iraqi officials said Tuesday that they expect more U.S. airstrikes near Baghdad in the coming days as the United States steps up its campaign against Islamic State militants.

The United States carried out two airstrikes Sunday and Monday in support of Iraqi forces, the U.S. Central Command said. One, southwest of Baghdad, signaled a widening area for the U.S. attacks, which have concentrated on Islamic State strongholds in northern Iraq.

The strikes coincided with a gathering of Western and Middle Eastern diplomats in Paris seeking to coordinate a broader strategy against the Islamic State in Iraq and Syria. The United States seeks to bring other nations into the air campaign.

The United States had held off increasing military assistance to Baghdad until a new broad-based government is formed, but Iraqi politicians are still wrangling over who should hold the key positions of ministers of defense and interior. Parliament rejected Prime Minister Haider al-Abadi’s candidates for the posts on Tuesday.

The United States coordinated Monday’s airstrikes with the Baghdad Operations Command, which oversees security in the capital, its spokesman, Brig. Gen. Saad Maan, said in a televised news conference.

“We selected the target,” he said. “There will be more targets in the future in the Baghdad belt.”

The strike hit Islamic State fighters near Sadr al-Yusufiyah, about 15 miles south of Baghdad, Lt. Gen. Qassim Atta, an Iraqi military spokesman, told the Agence France-Presse news agency. The area lies between the militant stronghold of Fallujah to the west and Jurf al-Sukkar, a flash-point area south of Baghdad.

The attack targeted a position used to fire on Iraqi security forces, the U.S. Central Command said. All aircraft exited the strike areas safely, it said.

Abadi had pledged to fill the defense and interior posts, and four other ministerial positions left open when the government was formed a week ago, by Tuesday. However, there has been fierce debate about who should steer the security posts amid the violence racking the country.

Shiite politician Riyad Ghareeb, a former minister of public works, was picked for interior minister but failed to gain the backing of the necessary majority of lawmakers in a vote on Tuesday.

The prime minister had pushed back against calls for former transport minister Hadi al-Ameri, who heads the Badr Brigade, a Shiite militia, to be given the role. The group’s political wing holds 20 seats in parliament and had threatened to withdraw from the government if it was not allowed to field its candidate for the position.

Addressing parliament, Abadi said numerous names were put forward over the past week. “There were so many different points of views,” he said. “Some blocs thought these positions should be for them; others said it should be strong, independent people. This I support.”

He urged lawmakers to back the candidates. “Now the situation is more challenging than a week ago, and in another week it will be harder and another week will be harder,” he said. “We can’t underestimate our enemy.”

Abadi’s pick for defense minister, Sunni politician Jaber al-Jaberi, also was rejected. Lawmakers complained that they had not been provided with information on the qualifications of the candidates.

Parliament will reconvene Thursday to vote on the positions again, according to Iraqi state television channel al-Iraqiya.

Mustafa Salim contributed to this report.