WASHINGTON, Oct 18: The commander of US forces in Iraq complained to the Army's brass in December that spare parts for tanks and other gear were in such low supply that it was threatening his forces ability to sustain combat operations , the army confirmed on Monday.

A spokesman said the army was aware of the supply problems and was working to correct them at the time of Lt Gen Ricardo Sanchez's Dec 4 letter to top Army leaders.

The Washington Post, which first reported on the letter, said Gen Sanchez wrote that army units in Iraq were "struggling just to maintain ... relatively low readiness rates" of key combat systems such as M1A1 Abrams Tanks, Bradley Fighting Vehicles, anti-mortar radars and Black Hawk helicopters.

He said his troops still needed protective inserts to upgrade 36,000 sets of body armor, the Post said.

"I cannot continue to support sustained combat operations with rates this low," Gen Sanchez wrote.

Lt Col Gerard Healy, an army spokesman, confirmed that Gen Sanchez, who commanded US forces in Iraq until this summer, had sent the letter to top army leaders complaining about the supply problems.

"The letter was not a surprise," he said. "The army staff as well as the army materiel command were already working on the issue."

The shortage of inserts for body armour was fixed soon after Gen Sanchez's letter and "just seven weeks later everybody had them", Healy said.

He said readiness levels of all combat systems mentioned in Gen Sanchez's letter are higher now than they were. The readiness rates of Abrams tanks are now over 90 per cent, he said.

Gen Sanchez' letter adds weight to charges by Senator John Kerry, the Democratic presidential candidate, that President George Bush's administration failed to adequately man and equip US forces to pacify Iraq after ousting Saddam Hussein.

The shortage of body armor in particular has been a long-running source of contention with families of soldiers serving in Iraq.

Mr Healy said the spare parts shortage arose after guerilla attacks suddenly intensified towards the end of last year.

Bombings of bridges disrupted resupply at a time when US forces were suddenly using tanks and other equipment at five times peacetime rates, he said. "Higher operating tempos is going to put stress on logistics needs," he said.-AFP