Tun Dr Mahathir Mohamad (pic) is "past his quiet stage" and has called for Prime Minister Datuk Seri Najib Tun Razak has to step down in order to save the country and Umno.
The former Prime Minister also said Najib's performance as premier is worse than his predecessor Tun Abdullah Ahmad Badawi.
"If Umno wants to be saved it has to change its leader. Who should replace him is up to Umno but he has to step down," said Dr Mahathir to reporters after giving an address at the "What Youth Should Know" leadership conference here on Saturday.
Dr Mahathir said he is "past his quiet stage" and felt he should speak up as the country's global reputation has "gotten worse" during Najib's tenure.
"I am not angry. I'm just thinking of our country. I have been keeping quiet over the last few years but I am past my quiet stage. Our country used to be known as one with a good administration. But not anymore. Now newspapers abroad are labelling Malaysia as the most corrupt country," said Dr Mahathir.
Dr Mahathir had also been critical of Badawi during his term as premier.
Earlier, Dr Mahathir also answered many current controversial issues during a no-holds barred question and answer session. Among the topics he addressed were on hudud law, the Altantuya Shaariibuu murder and racial relations.
Mahathir had also said that the government's biggest mistake was to put faith in material gain and giving handouts like the Bantuan Rakyat 1Malaysia (BR1M).
He was asked by a participant to identify the present government's biggest flaw and what he would do if he was in charge.
He said the present government should not make the people reliant on handouts but instead should be taught how to earn their own money.
"The BR1M thing is wrong as it makes people dependent on handouts. Giving money to the people and hoping they would vote for you is a wrong move. And they do not even vote for you. You also need to find more money for that purpose," said Dr Mahathir.
"If we keep relying on material gain then this would lead the country into a bad future," he added.