At least 30 Iraqis were killed Sunday -- a day after a deadly bomb attack in Baghdad -- as outgoing UN chief Kofi Annan said the bloodshed in the violence-wracked country was worse than a civil war.

Ten US troops were killed in Iraq over the weekend and three more are missing after a helicopter crashed in the restive west of the country, the US military said Monday.

Insurgents killed nine US troops across Iraq over the weekend, the military said Monday.

The military said the Marine Corps Sea Knight helicopter with 16 people on board crashed Sunday into a body of water in the western province of Al-Anbar.

Twelve people survived the crash while one marine was pulled out of the water but could not be revived.

"Search and recovery efforts are ongoing for the remaining three unaccounted servicemembers who have been listed as Duty Status Unknown," the military said.

The CH-46 Sea Knight entered service in the early 1960s and is one of the oldest models in use with the US military. The entire 218-strong fleet was briefly taken out of service in 2002 after faults were found.

Two soldiers were killed and two wounded by an explosion near their vehicle on Sunday during operations in northern Iraq.

Earlier Sunday the military had reported deaths of seven other servicemen across the war-torn country

The US military death toll in Iraq -- which dipped last month after a high in October during the Islamic holy month of Ramadan -- has climbed back to an average of three per day in the first four days of December.

Annan's remark came a few hours after President Jalal Talabani became the second Iraqi leader, after powerful Shia politician Abdel Aziz al-Hakim, to reject the UN chief's call for an international peace conference on Iraq.

Insurgents were back at work Sunday, when one wearing an explosive belt blew himself up next to a police station near the northern oil city of Kirkuk, killing three officers, Major General Torhan Yussef told AFP.

Farther south, at least 16 people were murdered in and around the restive town of Baquba, according to security and medical sources.

And Shia imam Taha Yassin, close to radical cleric Moqtada al-Sadr, was shot dead after evening prayers near his home in the southern city of Najaf.

Elsewhere 10 people were killed.

The US military reported the deaths of three more troops and confirmed that a pilot whose fighter plane crashed last week in northwestern Iraq was killed.

The fatalities took the military's losses since the March 2003 invasion to 2,888, according to an AFP count based on Pentagon figures.

On Sunday shell-shocked Iraqis were also mourning the 60 victims from Saturday's triple car bombing when blasts tore through a crowded shopping street at nightfall.

After more than three and a half years of mounting sectarian conflict, the attack, while vicious, was neither unexpected nor especially deadly -- more than 1,800 Iraqi civilians were slaughtered in November alone.

But each new massacre hammers a wedge deeper between Iraq's Sunni and Shia communities and chips away at the credibility of the country's beleaguered unity government and the US-led coalition force propping it up.

On Sunday American soldiers killed six suspected insurgents, two women and a child when they called in an air strike to dislodge gunmen from a house west of Baghdad late Saturday, the military said.

As the carnage continued Annan called the sectarian bloodshed worse than civil war.

In an interview with the BBC, Annan said: "When we had the strife in Lebanon and other places, we called that a civil war -- this is much worse."

Last week the world's top diplomat had called for an international conference on Iraq, an idea which was swiftly shot down by Talabani and Hakim.

"There's a political process ongoing in Iraq and there's a parliament which is the best in the region," Talabani said in a statement Sunday.

"We've become an independent sovereign state and it will be us who decides the future of our country."

Meanwhile, amid the bloodshed, there is a growing realisation in Washington that the current US strategy is failing and pressure is mounting for either a major change of course or a rapid pullout of the 138,000 US troops in Iraq.

Attention has focused on the Iraq Study Group -- a high-level bipartisan panel of experts headed by former secretary of state James Baker -- which is due to pass its recommendations to President George W Bush this week.

But on Sunday a leaked memo from former defence secretary Donald Rumsfeld, written in his final few days in office before resigning last month, revealed the administration has long known of the need for a change in the Iraq plan.

Rumsfeld's rambling three-page memo cites a shopping list of possible tactical and strategic changes, some of them mutually exclusive, but admits: "In my view it is time for a major adjustment.

"Clearly, what US forces are currently doing in Iraq is not working well enough or fast enough," Rumsfeld wrote, in a document passed to the New York Times and later confirmed as genuine by the Pentagon.

In particular, Rumsfeld favours placing more US trainers directly with Iraqi units, withdrawing other American troops from combat into five large bases by July next year and sending commandos to hunt down al-Qaeda and Iranian agents.

He also implicitly criticised other US government departments, saying the Pentagon should "give up" asking them for help and hire retired soldiers to advise Iraqi ministries.

Instead of spending money rebuilding cities like Fallujah that rebelled and were recaptured by US forces -- "rewarding bad behaviour" -- Rumsfeld suggested paying off political and religious leaders "as Saddam Hussein did".

US envoy in Iraq Zalmay Khalilzad largely appeared supportive of Rumsfeld's strategies.

"The political forces that want democratic order in Iraq that want to do the right thing, they need support, they need support from their own people, they need support from like-minded countries like the United States for them, because their enemies the extremists are getting resources from abroad."

"In order to level the playing field there is a need to provide help," he told CNN.

Judging by leaks to the US media, Baker will also recommend increasing the number of US army trainers, while withdrawing troops from combat and by early 2008 leaving only 70,000 soldiers in Iraq in a support role.

The White House may well be receptive to this idea, but seems opposed to another: that of reaching out to US foes Iran and Syria to persuade them to use their influence to calm the unrest in Iraq.