'Death to America', chants tens of thousands of Iraqis at Soleimani funeral march

Washington: Tens of thousands of Iraqis, many chanting "Death to America", Saturday mourned a top Iranian commander and others killed in a US drone attack that sparked fears of a regional proxy war between Washington and Tehran.

The killing of Iran's Major General Qasem Soleimani on Friday was the most dramatic escalation yet in spiralling tensions between Iran and the United States, which pledged to send thousands more troops to the region.

Iraqi political leaders and clerics attended the mass ceremony to honour 62-year-old Soleimani and the other nine victim of the pre-dawn attack on Baghdad international airport.

US President Donald Trump said he had decided to "terminate" Iran's military mastermind to prevent an "imminent" attack on US diplomats and troops.

"We took action last night to stop a war," he insisted. "We did not take action to start a war."

But a furious Iran has vowed revenge for the killing of Soleimani, the chief architect of its military operations across the Middle East.

"The response for a military action is a military action," Iranian ambassador to the United Nations Majid Takht Ravanchi told CNN, calling the strike an "act of war".

"By whom, by when, where? That is for the future to witness."

In the hours after the strike, the US reached out to Iran, with which it has had no direct diplomatic ties for decades.