Eleven Sunni insurgent groups have offered an immediate halt to all attacks � including those on American troops � if the United States agrees to withdraw foreign forces from Iraq in two years, insurgent and government officials told The Associated Press on Wednesday.

Withdrawal is the centerpiece of a set of demands from the groups, which operate north of Baghdad in the heavily Sunni Arab provinces of Salahuddin and Diyala. Although much of the fighting has been to the west, those provinces are increasingly violent and attacks there have crippled oil and commerce routes.

The groups who've made contact have largely shunned attacks on Iraqi civilians, focusing instead on the U.S.-led coalition forces. Their offer coincides with Prime Minister Nouri al-Maliki's decision to reach out to the Sunni insurgency with a reconciliation plan that includes an amnesty for fighters.

The Islamic Army in Iraq, Muhammad Army and the Mujahedeen Shura Council � the umbrella group that covers eight militant groups including al-Qaida in Iraq � were not party to any offers to the government.

Naseer al-Ani, a Sunni Arab politician and official with the largest Sunni political group, the Iraqi Islamic Party, said that al-Maliki should encourage the process by guaranteeing security for those making the offer and not immediately reject their demands.

"The government should prove its goodwill and not establish red lines," al-Ani said. "If the initiative is implemented in a good way, 70 percent of the insurgent groups will respond positively."

Al-Maliki, in televised remarks Wednesday, did not issue an outright rejection of the timetable demand. But he said it was unrealistic, because he could not be certain when the Iraqi army and police would be strong enough to make a foreign presence unnecessary for Iraq's security.

In Washington, Defense Secretary Donald Rumsfeld said that President Bush's "view has been and remains that a timetable is not something that is useful. It is a signal to the enemies that all you have to do is just wait and it's yours.

"The goal is not to trade something off for something else to make somebody happy, the goal is to succeed," he said.

Bush has said U.S. troops will remain in Iraq for years to guarantee the success of the new Iraqi government. However, American military officials have said substantial reductions of the current force of 127,000 U.S. troops could be made before the end of 2007.

Eight of the 11 insurgent groups banded together to approach al-Maliki's government under The 1920 Revolution Brigade, which has claimed credit for killing U.S. troops in the past. All 11, working through intermediaries, have issued identical demands, according to insurgent spokesmen and government officials.

The officials spoke on condition of anomymity because of the sensitivity of the information and for fear of retribution.

The total number of insurgents is not known, nor how many men belong to each group. But there are believed to be about two dozen insurgent organizations in Iraq, so the 11 contacting the government could represent a substantial part of the Sunni-led insurgency.

Al-Maliki's offer of amnesty for insurgents would not absolve those who have killed Iraqis or American coalition troops. But proving which individuals have carried out fatal attacks would, in many � if not most � cases, be a difficult task.

The issue is extremely sensitive in the United States, which has lost more than 2,500 uniformed men and women in Iraq, many to the insurgents' bombs and ambushes.

Coinciding with al-Maliki's attempts to bring Sunni Arabs to the bargaining table, U.S. Ambassador Zalmay Khalilzad held talks Tuesday in Saudi Arabia with King Abdullah. The Saudis have influence with many Sunni insurgents in Iraq.

Al-Maliki also set up an e-mail account to communicate with insurgents, flashing the address on the screen during a broadcast Sunday night.

For al-Maliki, reaching out to the Sunnis risks heightening tensions in his ruling coalition of mostly Shiite Muslim political groups. Al-Maliki is said to be increasingly disenchanted with the close ties between the country's most powerful Shiite organization and Iran, which is ruled by a Shiite theocracy.

Abdul Aziz al-Hakim, leader of the Supreme Council for the Islamic Revolution in Iraq, a Shiite group with historic ties to the Iranians, favors close relations with Iran. Many of Iraq's most powerful Shiite politicians and religious figures spent years in Iranian exile during Saddam Hussein's regime.

In addition to the withdrawal timetable, the Iraqi insurgents have demanded:

� An end to U.S. and Iraqi military operations against insurgent forces.

� Compensation for Iraqis killed by U.S. and government forces and reimbursement for property damage.

� An end to the ban on army officers from Saddam's regime in the Iraqi military.

� An end to the government ban on former members of the Baath Party � which ruled the country under Saddam.

� The release of insurgent detainees.

The 1920 Revolution Brigades, the umbrella for seven other groups, was established in the so-called Sunni Triangle north and west of Baghdad shortly after the 2003 U.S.-led invasion. Its name refers to Iraq's historical fight against British colonialism.

The group has claimed responsibility for attacking American troops, including the downing of two helicopters in 2004.

"If they set a two-year timetable for the withdrawal we will stop all our operations immediately," said the leader in a telephone interview with the AP. The man, who refused to give his name for security reasons, spoke from the telephone of one of the mediators. Others present made similar remarks.

Besides the 1920 Revolution Brigades, the eight include Abtal al-Iraq (Heroes of Iraq), the 9th of April Group, al-Fateh Brigades, al-Mukhtar Brigades, Salahuddin Brigades, Mujahedeen Army and the Brigades of the General Command of the Armed Forces. The three other groups are small organizations that also mainly operate in areas north of Baghdad.

In other developments Wednesday:

� Russian President Vladimir Putin ordered his special services to hunt down and "destroy" the killers of four Russian Embassy workers in Iraq.

� National Security Adviser Mouwafak al-Rubaie said a key al-Qaida suspect wanted in the bombing of a Shiite shrine � a Tunisian identified as Yousri Fakher Mohammed Ali � was captured. However, he said the Iraqi mastermind of the attack that pushed the country to the brink of civil war, Haitham Sabah Shaker Mohammed al-Badri, was at large. There never was a claim of responsibility for the bombing.