Vice President Biden welcomes Iraqi Prime Minister Nouri al-Maliki to the Naval Observatory on Oct 30. (Mark Wilson/Getty Images)

An alarming spike in sectarian violence in Iraq is pinning the Obama administration between its goal of strengthening Prime Minister Nouri al-Maliki in his fight against Sunni extremists and pressuring the Shiite-led government to stop what the United States considers the political mistreatment of Sunnis.

As Maliki makes his first visit to Washington in more than two years this week, security concerns have largely eclipsed Washington’s political quarrels with him.

Although administration officials insist that they are holding Maliki accountable for his failure to govern inclusively, the rapid strengthening of al-Qaeda militants and the collapse of security along Iraq’s long border with Syria are the main focus of his discussions with U.S. officials. He is spending much of his time this week lobbying Congress to free up security money and unfreeze weapons sales that the administration has already approved.

Maliki’s Oval Office meeting with President Obama on Friday may yield an announcement of wider U.S. cooperation to help Iraq confront a resurgent and well-armed al-Qaeda affiliate.

“There are quite urgent requirements from Iraq’s security situation,” Lukman Faily, Iraq’s ambassador to Washington, said in an interview.

“We will be waiting for fuller responses from our American friends to tell us what they can offer.”

The network once known as al-Qaeda in Iraq is blamed for suicide bombings against Shiite civilians. It also represents a threat to the U.S. goal of democratic change in Syria and beyond. The group now calls itself the Islamic State of Iraq and Syria, with a growing presence in the neighboring country.

Killings in Iraq are now on pace to match the levels of 2008, the year that sectarian violence bordering on a civil war began to abate. A rise in violence that began in the spring has eclipsed the security gains made in the past five years.

The old Sunni-Shiite split has reemerged as the main internal threat in Iraq, overtaking a separate division between Kurds and Arabs. Nearly 600 people have been killed in sectarian attacks across Iraq this month; more than 5,300 Iraqis have been killed this year.

Maliki met for two hours Wednesday with Vice President Biden, long the administration’s leading voice on Iraq. Maliki made an urgent case for U.S.-made Apache attack helicopters, asking for Biden’s help in overcoming congressional opposition to sale of the aircraft, which can shoot precision munitions like those fired by drones and track enemy movements with powerful cameras.

Bipartisan skeptics in Congress are holding up a possible Apache sale, in protest of Maliki’s political decisions and out of concern that his forces might turn the Apaches on internal opponents who are not affiliated with al-Qaeda or other terrorist groups. Congressional critics also accuse Maliki of turning a blind eye to Iranian aircraft flying over Iraq to supply Syrian President Bashar al-Assad with weapons and fighters.

As Maliki arrived Tuesday evening, six influential senators blasted his government as beholden to Shiite Iran’s “malign influence” and said Maliki’s “mismanagement of Iraqi politics” risks tipping the country back toward civil war.

Democrats Carl Levin (Mich) and Robert Menendez (N.J.) and Republicans John McCain (Ariz.), James M. Inhofe (Okla.), Bob Corker (Tenn.) and Lindsey O. Graham (S.C.) urged Obama to take a hard line with Maliki on political reconciliation.

If Maliki adopts a new, inclusive strategy, the United States would be ready to provide support to help that strategy succeed, the senators wrote.

Maliki knows he will get an earful from leaders of the House and Senate foreign affairs panels, Faily said.

“We are aware of that, yes,” he said dryly. “We’ve done our homework.”

In addition to his private assurances to Congress, Maliki will speak Thursday at the U.S. Institute of Peace about political reconciliation.

The Obama administration is quietly supporting the Apache sale, because of the aircraft’s unique counterterrorism capabilities, U.S. and Iraqi officials said. The administration is also exploring other ways to help Maliki confront militants, including increased surveillance and intelligence cooperation.

U.S. officials point to a stunning jailbreak in the summer as part of the rationale for expanding counterterrorism help to Maliki. More than 500 suspected militants were freed in the well-planned assault on the Abu Ghraib prison, reversing years of U.S. and Iraqi efforts to round up leaders of the al-Qaeda affiliate.

“This is really a major and increasing threat to Iraq’s stability, it’s an increasing threat to our regional partners, and it’s an increasing threat to us,” a senior administration official told reporters in a briefing on Wednesday.

“It is a fact now that al-Qaeda has a presence in western Iraq, and it has a presence in terms of camps and training facilities and staging areas that the Iraqi forces are unable to target effectively,” the official said, noting that this is partly because the militants are increasingly equipped with heavy weaponry from Syria.

The official spoke on the condition of anonymity under ground rules set by the administration.

The main argument to Congress, U.S. and congressional officials said, is that strengthening the Iraqi government’s hand against militants makes the whole region safer and helps protect U.S. economic and security interests in Iraq and elsewhere.

The administration’s argument to Maliki is that the counter­terrorism support is of a piece with U.S. demands that he continue what administration officials cite as initial progress in repairing some of the political rift with Sunnis and Kurds.

“We are saying to him clearly, ‘Yes, we want to help you out as much as we can, but this is not a one-dimensional situation,’ ” a senior State Department official said.

“Part of solving the security situation is solving the political situation.”

The official spoke on the condition of anonymity to describe internal discussions.

Maliki is joined on this visit by his Sunni defense minister and Kurdish foreign minister, in a symbolic show of unity that the delegation hopes can help overcome congressional doubts.