Prime Minister Dr Mahathir Mohamad has expressed fear that a power struggle may emerge in his United Malays National Organisation (Umno) party after he steps down, a report said Sunday.

"I do not think there would be anyone who will challenge Abdullah Ahmad Badawi. But until the issue of (who becomes the) deputy president of Umno is resolved, there will be a power struggle for the number two post," Mahathir was quoted as saying in the Malay-language daily Mingguan Malaysia.

Abdullah, 63, is the political heir to the 77-year-old Mahathir, who has vowed to bow out in October after 22 years in power.

Mahathir said he was confident his deputy would take over Umno, the backbone of the National Front coalition of ruling racially based parties.

"I do not think Abdullah would be challenged. I would be sad if this happens," he said. "If they do it, they will lose."

He believed there would be infighting over other positions, such as for deputy and vice president.

He said, however, the deputy would be chosen by Abdullah when he takes power. - AFP