Prime Minister Dr Mahathir Mohamad, who has been in office since 1981, has said he has no intention of holding his position for life.

"The world will not end if I am not prime minister. I hope no one will hold on to the belief that I will remain as prime minister for as long as I live," Asia's longest serving ruler told a Mayday rally on Wednesday, the New Straits Times reported.

"While I appreciate the confidence the people have in me, when the time comes, I will have to go," the 76-year-old said.

Mahathir said he wanted to relax and do the things he wanted to do.

The premier, who has been in office since July 1981, has repeatedly said that his deputy Abdullah Ahmad Badawi will replace him when he does retire.