Two weeks before U.S. midterm elections, American officials unveiled a timeline Tuesday for Iraq's Shiite-led government to take specific steps to calm the world's most dangerous capital but said more U.S. troops might be needed to quell the bloodshed.

U.S. officials previously said they were satisfied with troop levels and had expected to make significant reductions by year's end. But a surge in sectarian killings, which welled up this past summer, forced them to reconsider.

At a rare joint news conference with the American ambassador, the top U.S. commander in Iraq, Gen. George Casey, said additional U.S. troops could come from inside or outside Iraq to "improve basic services for the population of Baghdad."

"Now, do we need more troops to do that? Maybe. And, as I've said all along, if we do, I will ask for the troops I need, both coalition and Iraqis," Casey said.

The military has expressed disappointment over its two-month drive to cleanse the capital of Sunni insurgents and Shiite militia fighters and death squads. But the Americans also say that for the situation to improve, the Iraqi government must make political concessions to minority Sunnis.

The timeline plan grew out of recent Washington meetings at which the Bush administration sought to reshape its Iraq policy amid mounting U.S. deaths and declining domestic support for the 44-month-old war. The plan was made public a day after White House press secretary Tony Snow said U.S. was adjusting its Iraq strategy but would not issue any ultimatums.

U.S. officials revealed neither specific incentives for the Iraqis to implement the plan nor penalties for their failure to do so. U.S. Ambassador Zalmay Khalilzad said Iraqi leaders had agreed to the timeline, benchmarks heavily laden with enticements to Sunni insurgents.

The lack of any real political consensus even among Shiites, however, has made it extremely difficult for Iraqi leaders to keep deadlines; for example, they missed targeted dates on naming a government and in moving forward on constitutional amendments. Moreover, Tuesday's declarations lacked specifics on how to accomplish the goals.

At the news conference with Casey, Khalilzad said the timeline would require Prime Minister Nouri al-Maliki's government to set dates by the end of the year for completing six key tasks.

Five of the markers are clearly designed to mollify Sunni Arabs, the Muslim sect that makes up the bulk of the insurgency and is responsible for most American deaths in Iraq.

The plan seeks deadlines for passing a law that would guarantee the sharing of Iraq's oil wealth, amending the constitution, turning an anti-Baathist organization into a reconciliation body, disbanding Shiite militias and setting a date for provincial elections -- all key issues for Sunnis.

The de-Baathification Commission was established after the toppling of Saddam Hussein to ensure that members of the dictator's political organization did not hold government positions.

The sixth measure called for "increasing the credibility and capability of Iraqi forces."

Casey said Iraqi forces would be "completely capable" of controlling the country within the next 1 1/2 years.

"We are about 75 percent of the way through a three-step process in building those (Iraqi) forces," the general said. "It is going to take another 12 to 18 months or so until I believe the Iraqi security forces are completely capable of taking over responsibility for their own security. That's still coupled with some level of support from us."

Casey's estimate of when the Iraqi army will be ready was noteworthy because it has not changed even as the security situation in the country has deteriorated. Iraqis are now being killed at a pace of more than 40 each day in sectarian fighting and revenge killing.

Complicating the matter has been the recent outbreak of sustained Shiite-on-Shiite violence in the once relatively calm south of the country.

To curb the spreading and increasingly brutal killings, Khalilzad said the United States was "inducing Iraqi political and religious leaders who can control or influence armed groups in Baghdad to agree to stop sectarian violence," an apparent reference to recent secret talks the United States has conducted with Sunni insurgents.

Al-Maliki has repeatedly said he would rein in Shiite militias but so far has taken little public action beyond a decision to move aside two police commando leaders. He issued a statement on Monday saying the military had been ordered to take action against any illegal armed group, but the declaration, like the timeline introduced on Tuesday, lacked detail.

His national security adviser, Mouwafak al-Rubaie, sought to add weight to the prime minister's directive in an interview with CNN. He was, however, equally fuzzy about what action would be taken.

"The Iraqi security forces are going to take on anyone who challenges" them," al-Rubaie said.

Khalilzad said he had assurances from al-Maliki that radical anti-American Shiite cleric Muqtada al-Sadr would disband his Mahdi Army. But al-Sadr draws much of his power from his control over the heavily armed fighters. And al-Maliki draws much of his support from al-Sadr.

For that reason, disbanding the feared militia group appears to be a promise that is unlikely to be kept in the near term. Such a move would leave the other main Shiite militia, the Badr Brigade of the Supreme Council for the Revolution in Iraq, or SCIRI, in a dominant position.

Al-Sadr and SCIRI leader Abdul-Aziz al-Hakim maintain a sharp rivalry for power over Iraq's Shiite majority. Logic dictates that both militias be disbanded simultaneously, which appears highly unlikely.

While Shiite militias and death squad violence represent a major security problem, curbing them would still leave the other half of the equation unsolved -- the continued vibrancy of the Sunni insurgency that has been attacking Americans with a vengeance since summer 2003.

The timeline appeared, therefore, largely directed at luring the Sunni establishment away from violence and into the political process.

October has been the deadliest month this year for American forces. The military Tuesday announced the deaths of two more U.S. Marines, a sailor and a soldier. Since the start of the war, 2,801 U.S. service members have died in Iraq, according to an Associated Press count.

Also Tuesday, the military said it had found no sign of a U.S. Army translator missing after he was believed to have been kidnapped the night before in Baghdad. Troops continued to search the city's downtown on foot and by air.

The military said the soldier, a linguist who was not identified by name, was last seen inside Green Zone on Monday. He was then believed to have left to visit Iraqi relatives in the city.

He was apparently at the relatives' house when three cars carrying masked gunmen arrived. The soldier was handcuffed and driven away. One of the kidnappers then called one of the relatives using the kidnap victim's cell phone, the military said. It didn't say if ransom was demanded.

Across the country, police reported that 11 Iraqis, including two policemen and a soldier, were killed in bombings and shootings; authorities said 14 bodies were found dumped or pulled from the Tigris River.