The United States and Iraq are drawing up a campaign plan for offensive operations by Iraqi ground forces to gradually reclaim towns and cities that have been occupied by the Islamic State, according to a senior administration official.

The plan, described as methodical and time-consuming, will not begin in earnest for several months and is designed to ensure that Iraqi forces­ do not overextend themselves before they are capable of taking and holding territory controlled by the militants.

It may also include U.S. advisers in the field with the Iraqis, should that be recommended by American military commanders, said the official, who updated reporters on administration strategy on the condition of anonymity under rules imposed by the White House. The advisers, the official said, would not participate in combat. President Obama has said repeatedly that no U.S. ground forces would be deployed to Iraq.

With few exceptions, the Iraqi army has concentrated largely on defense and efforts to prevent the Islamic State from claiming ever-more territory since early June when the militant group took over Mosul, Iraq’s second-largest city, and began moving southward.

Despite some government gains, aided since early August by U.S. airstrikes, the militants control about one-third of Iraq, stretching from near Baghdad to the northwest, and across western Anbar province to the Syrian border.

Turkish Kurds hold funerals for those killed by fighting against Islamic State militants in the Syrian town of Kobane. One of the mourners says the fighting “is almost a genocide.” (Reuters)

In August, Obama also authorized airstrikes against Islamic State targets in western and northern Syria. Over the past few weeks, world attention has focused on the Syrian town of Kobane, along the Turkish border, where Islamic State forces­ have threatened to overrun besieged Syrian Kurdish defenders.

Following a U.S. military airdrop of weapons, ammunition and medical supplies to the Syrian Kurds on Sunday, Iraqi Kurdish fighters, called the pesh merga, are expected to come to their assistance. The administration official said that the Syrian Kurds, while politically at odds with their Iraqi brethren, have agreed to accept an influx of pesh merga fighters. Details of the size and composition of the Iraqi Kurdish force, which is expected to cross into Kobane from Turkey, are to be finalized in the next few days.

But the administration has said repeatedly that Iraq remains its main concern. Obama said last month that in addition to the airstrikes, his strategy includes trainers and advisers for the Iraqi military, which largely fled from advancing Islamic State forces­ in Mosul, and the installation of a more inclusive Iraqi government under which the country’s principal Muslim sects — Sunnis, Shiites and Kurds — could unite.

A new government, led by Shiite Prime Minister Haider al-Abadi, was installed in early September. But delays in appointments to the key posts of defense and interior ministers had threatened to set back any political progress. Those posts were filled Saturday, when the Iraqi parliament approved Khaled al-Obeidi, a Sunni lawmaker from Mosul, for the defense post and Mohammed Salem al-Ghabban, a Shiite member of parliament, as interior minister.

Abadi, the administration official said, has pledged to meet concerns of Iraq’s Kurdish regional government over control of its oil resources and to help develop government-paid local defense forces­ in Sunni-dominated Anbar. But those pledges were also made by Abadi’s ousted predecessor, former prime minister Nouri al-Maliki, and have remained unfulfilled for years.

In extensive diplomatic and military interventions, the Obama administration has tried to persuade Iraqis to quickly address their differences — or put aside those that cannot be immediately resolved — in the face of the existential threat posed by the Islamic State.

Abadi must also walk a fine line between his government’s other principal patron, Iran, where he plans to visit this week.

Many of Anbar’s Sunnis remain hesitant to commit to the government, torn between their dislike of the militants and a greater disdain for the Shiite domination they have endured in recent years.

The success of any plan to retake Iraq from the Islamic State depends on simultaneous progress in all of these long-problematic areas. The Pentagon has assessed that, at best, only about half of Iraqi army units are currently capable of effective fighting, and Abadi has only just begin replacing inept and corrupt commanders installed under Maliki.

As described by the senior official, the offensive campaign will be conducted under a specific timeline, village by village, with any attempt to dislodge entrenched Islamic State forces­ in Mosul likely to be delayed until well into next year. At the same time, any plan risks being derailed by the militants, who have their own strategy to continue advancing.

And until the fledgling government can convince all Iraqis that it has broken conclusively with the past, the Kurdish region will not give up its aspirations for independence, and Sunnis will continue to doubt its nonsectarian sincerity.