At least 135 U.S. troops died in November, according to casualty reports available Tuesday.
The worst month was April when 135 died as the insurgence flared in Fallujah and elsewhere in the so-called Sunni Triangle where U.S. forces and their Iraqi allies lost a large measure of control.
On Tuesday, a suicide bomber detonated a car packed with explosives next to a U.S. convoy on Baghdad's dangerous airport road and several casualties were seen lying next to a damaged vehicle, witnesses and authorities said.
In the northern town of Beiji, a car bomb exploded near a U.S. patrol Tuesday, killing four Iraqi civilians and injuring 19 people, two of them American soldiers, the military said. Another soldier from the 1st Infantry Division was wounded when insurgents fired a rocket-propelled grenade at a tank south of Beiji.
A U.S. Army soldier died from injuries suffered after a roadside bomb exploded late Monday next to his patrol north of Baghdad.
Amid the violence, interim Prime Minister Ayad Allawi was heading to Jordan to meet with Iraqis living outside the country to encourage them to take part in the Jan. 30 election in a bid woo support away from the insurgency. However, he ruled out a full-blown conference with insurgent enemies.
In other developments:
In the suicide attack, police Capt. Talib al-Alawani said a bomber drove his car into a U.S. convoy on the airport road, scene of near daily attacks against U.S. military and Western targets. The U.S. command confirmed that the attack occurred but had no further details.
Several casualties were seen lying next to a damaged vehicle, according to an eyewitness who arrived on the scene before troops sealed off the stretch of road where the blast occurred. A military ambulance drove up minutes later to evacuate the casualties.
The highway, which multinational troops use daily to commute between the huge military base at the airport and Baghdad's center, is considered one of the most dangerous roads in Iraq. The British Embassy announced Monday that its staff would no longer be permitted to travel on the road.
In Beiji, a U.S. military statement said the two attacks occurred about 9:10 a.m., but it did not give the condition of the wounded nor specify whether the car bomb was a suicide attack.
U.S. troops backed by tanks and helicopter gunships launched a series of attacks on parts of Beiji earlier this month to try to root out insurgents from the town, located on the major supply route from Baghdad to the north.
Meanwhile, an official with Allawi's office said the prime minister will travel Tuesday to Jordan to meet with Iraqis outside the country as part of a dialogue on the country's future.
Allawi was to appear later Tuesday before the Iraqi National Council, a government advisory body, where he was expected to answer questions about the meeting. The official, speaking on condition of anonymity, would not identify the Iraqi groups who would take part in the meeting.
The meeting is seen as an effort to reach out to various Iraqi groups to encourage broad participation in the Jan. 30 election. Iraqi officials have insisted Allawi would not meet with "terrorists," meaning insurgent leaders.
Foreign Minister Hoshyar Zebari told the National Council on Tuesday that the government recognized the need to "widen the scope of participation" in the election to those groups "that renounce violence and terrorism."
Zebari said Allawi would meet with about 25 to 35 "personalities," mostly from the Ramadi area of Anbar province.
"We still think that national reconciliation is necessary and vital but we also make a distinction," Zebari said. "If there are people who are accused and are known for what they have committed ... these people should be tried according to the laws."
Military offensives in Fallujah and elsewhere have made November the second deadliest month for U.S. troops since the March 2003 invasion, with at least 134 American dead.
The Pentagon, meanwhile, said Monday the U.S. military death toll in Iraq since the U.S.-led invasion in March 2003 stands at 1,251. That is up 21 since the Pentagon last reported a total on Nov. 24.