Beijing - The foot injury that forced China's star hurdler Liu Xiang to withdraw from this year's Olympic Games is looking more likely to need surgery that could keep him out of competition for six months, Chinese media said on Friday.

Liu, 24, returned to China on Wednesday after consulting US medical experts but had still not made a final decision on whether to opt for surgery, the official China Daily and other media said.

The former 110-metres hurdles world record holder and gold medallist at the 2004 Olympics in Athens had travelled to the United States to seek further medical opinions after Chinese doctors advised surgery to repair tendon damage.

Liu and his coach Sun Haiping were still hoping they could find an alternative to surgery, the reports said.

Liu said on his official website that the US doctors were "optimistic" and that the injury might not be "that serious".

"According to experts in the US, the inflammation was caused by calcification in his tendon and most of this can be eliminated by surgery," Titan Sports quoted Feng Shuyong, the head coach of the Chinese athletics team, as saying.

"He should need about six months to recover," said Feng, who travelled to the United States with Liu.

"We will proceed very cautiously to reduce any risk of things going wrong, he said.

"The decision (on surgery) may take some time," Titan Sports quoted Feng as saying. (dpa)