Kuwait returned to Iraq on Monday the remains of 55 Iraqi soldiers killed in the Gulf War in 1991, a month after they were found in a mass grave.

Iraqi troops shouldered the remains in coffins draped with Iraqi flags during a ceremony in the town of Safwan along the border in a sign of cooperation between neighbours that have had a testy relationship since Saddam Hussein's army invaded Kuwait nearly two decades ago.

Mahdi al-Temimi, an official in Iraq's Human Rights Ministry, said the remains were found together in a grave in the Mutlaa area in northern Kuwait and 12 of the 55 had been identified.

"The rest are still unknown and we hope that we will identify them by using DNA tests and tissue analysis," Temimi said.

"This is the fifth time we have received remains of Iraqi soldiers from Kuwait and we have received more than 100 so far."

A Kuwaiti embassy official said Iraq had handed over the remains of 280 Kuwaitis killed during the Gulf War.

More than 360 Kuwaitis and others who lived in Kuwait when Iraq invaded are still unaccounted for. – Reuters