The Malaysian government has denied ordering ex-premier Dr Mahathir Mohamad to back off from his role as negotiator in the Muslim insurgency in Thailand.

Foreign Minister Syed Hamid Albar said Mahathir was never an official mediator, but that Malaysia had asked him to use his personal contacts to help bring peace in the Thai south.

"He never had an official role. I was the one who asked him to do whatever he could since he was invited by Thaksin Shinawatra, then the Thai leader," Syed Hamid said according to The Star daily.

"We did not make any objection. It takes the pressure off the Malaysian government because during Thaksin's time it was a very sensitive issue."

Mahathir revealed in October that he had brokered landmark talks in late 2005 between Thai officials and Muslim separatists, to help resolve the three-year conflict on Malaysia's doorstep which has left 1,800 people dead.

But in January he said that while he would like to do more, he had been told to back off from his role as intermediary. He would not specify who had issued the advice.

The government of mainly-Muslim Malaysia has volunteered to play a bigger role in resolving the crisis.

However, its relationship with Mahathir has collapsed in the past year after the former leader made strident attacks on the administration of Prime Minister Abdullah Ahmad Badawi, his hand-picked successor who took over in 2003.