Now that he is out of Umno, former prime minister Dr Mahathir Mohamad no longer has the right to criticise the party leadership, Umno veteran Mustapha Yaakob says.

"He is no longer a party member and constitutionally speaking, he has no right to talk about Umno or attack Umno leaders.

"It is true that as a Malaysian he has the right to express his views, but we ask that since he has decided to leave, he should let bygones be bygones," Mustapha told Malaysiakini .

The Umno veteran also hoped that Mahathir would truly retire from politics and focus his efforts and energy instead on the various NGOs that he is patron of.

"We hope that he will truly retire from politics and focus on other NGO work," he said.

Mustapha added that as a statesman, Mahathir should quit while he is still respected, so that he would be remembered as an eminent personality.

Furthermore, he said, the former prime minister of 22 years may want to spend time with his family as well.

"If he were to leave us, we want him to be remembered as a respected statesman. Enough is enough. He is of a matured age. He may want to spend time with his family and focus on his children and grandchildren. That is what we hope," Mustapha added.

On Monday, Mahathir and his wife Dr Siti Hasmah Mohamad Ali announced that they are both quitting Umno , for the second time, in their protest against the leadership of Prime Minister Najib Abdul Razak.

The former prime minister said he made the decision because Umno was no longer the party he knew and that it has been remade from a party that fights for the nation to one that fights only for Najib.