A suicide bombing and shelling in Iraq's Anbar province killed six people as security forces pressed an assault Friday against militants for territory the government lost weeks ago.

As the violence raged, a US defence official said the military is planning to train Iraqi troops in a third country to help counter a resurgence of Al-Qaeda-linked militants.

Unrest in Anbar and elsewhere in Iraq has already killed more than 600 people this month, fuelling fears the country is slipping back into all-out sectarian war with little appetite for political compromise ahead of an April general election.

UN chief Ban Ki-moon and other diplomats have urged Baghdad to pursue political reconciliation, but Prime Minister Nuri al-Maliki has ruled out dialogue with militants, and the authorities have instead trumpeted police and army operations.

On Friday, thousands of elite security forces pressed an assault on Albubali, a rural area where officials say a large number of anti-government fighters are holed up.

The area of farmland and villages lies between Ramadi and Fallujah, the two cities in the western desert province at the centre of the crisis.

Security forces are also seeking to recover the bodies of eight of their own who have been killed in militant attacks.

Air support that initially accompanied the operation has been withdrawn for fear the militants have anti-aircraft weapons, two policemen told AFP.

They added that security forces, backed by tanks, had so far recovered the bodies of six gunmen killed in the offensive, but progress was limited by snipers.

A large swathe of Ramadi and all of Fallujah, both former insurgent bastions, fell from government control late last month. That marked the first time anti-government fighters have exercised such open control in major cities since the height of the insurgency that followed the US-led invasion of 2003.

The Al-Qaeda-linked Islamic State of Iraq and the Levant (ISIL) has been involved in the fighting alongside anti-government tribal fighters, while Baghdad has recruited its own allies among the province's powerful tribes.

In Washington, a defence official speaking to AFP on condition of anonymity said that pending an agreement with Jordan or another nation, the training of Iraqi troops by the US military was "likely" to go ahead as both Baghdad and Washington support the idea.

Maliki's high-stakes gamble

Maliki said in an interview published Thursday by the Washington Post that he had asked the United States for weapons and counter-terrorism training.

"We are going to ask for training, in some areas we need training, especially for our counter terrorism units," he said, adding that Iraqi soldiers could go to Jordan for training.

Pentagon spokesman Colonel Steven Warren said in Washington that Maliki had requested weapons and ammunitions. The defence official said "several thousand" M-16 and M-4 assault rifles and ammunition would be sent to Iraq.

On the ground, the army has largely focused its latest efforts on militant bases outside Ramadi and Fallujah, while loyalist militiamen and police have taken part in the fight to retake Ramadi.

Fighting originally erupted in the Ramadi area on December 30, when security forces cleared a year-old Sunni Arab protest camp.

It spread to Fallujah, and militants moved in and seized the city and parts of Ramadi after security forces withdrew.

In the latest fighting, shelling in Fallujah erupted late Thursday and continued until the early hours of Friday, killing another three people, a doctor at a local hospital said.

And in other violence Friday an off-duty soldier was killed and three others wounded in a gun attack near the main northern city of Mosul.

Diplomats have called on the Shiite-led authorities to address longstanding grievances within the Sunni minority to undercut support for militants.

But with a parliamentary election due on April 30, Maliki has taken a hard line and ruled out dialogue, a high-risk gamble that could affect more than just his bid for re-election.

"If Maliki succeeds, and the security situation in Anbar improves, he will have a better chance at winning the election," said Ihsan al-Shammari, a professor of politics at Baghdad University.

"But if he fails? That will not only affect Maliki's political future. It will threaten the political process."

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