Known for his staunch opposition towards street rallies in the past, Dr Mahathir Mohamad now appears to make an exception when it concerns Prime Minister Najib Abdul Razak.

Responding to a question on whether he supported such actions, the former premier said it is needed when a government does not care for the law.

"If the government is not concerned about the law, you have to use demonstrations. It is the last option.

"Look at (Ferdinand) Marcos. When he was ruining Philippines, they had to overthrow him," he told reporters at a restaurant near Central Market in Kuala Lumpur this afternoon.

Mahathir and his wife Dr Siti Hasmah Ali had taken the KTM Komuter train to the city to express solidarity for those participating in Bersih 4.

However, the former premier said he supported the people, but not Bersih.

This is Mahathir's second appearance at Bersih 4. He spent six-minutes at the main rally grounds near Dataran Merdeka last night before leaving.

It is understood that this is the first time Mahathir had attended a rally of this nature.

Mahathir, who ruled Malaysia for 22 years, has turned into Najib's harshest critic, particularly over the latter's handling of the 1MDB controversy.