Former MCA president Dr Ling Liong Sik has joined former prime minister Dr Mahathir Mohamad in publicly calling for Najib Abdul Razak's removal as prime minister.

"I agree with Mahathir. Because he (Najib) has taken people's money and put it in his own personal accounts," Ling told a press conference after attending the 11th Festival of Minds at Tunku Abdul Rahman University College in Kuala Lumpur today.

Ling said this when asked whether he agreed with Mahathir's relentless demands for Najib to quit as prime minister.

Najib is embroiled in controversy over the deposit of RM2.6 billion in his personal accounts.

The prime minister has denied taking public funds for "personal gain" while his supporters claim the massive deposits were "political donations" for Umno from the Middle East.

Ling ( photo ) for the first time also elaborated on his participation in the Bersih 4 rally in Perth, saying he wants to see Najib out.

"I attended the Bersih 4 rally in Perth, Australia, to support a vote of no confidence against Najib as he had taken people's money and put it into his personal accounts. I feel that should not happen," said Ling.

Mahathir has, since April, openly declared war on Najib, demanding that he resign lest the ruling coalition is defeated in the next general election.

His associates, such as former Batu Kawan Umno vice-chief Khairuddin Abu Hassan and lawyer Matthias Chang, have also helped international investigators to initiate money laundering cases against Najib.

Khairuddin, whose police reports across the globe have triggered investigations in Switzerland, Hong Kong, UK and the US relating to accounts linked to Najib and 1MDB, is now under detention under the Security Offences (Special Measures) Act 2012 for allegedly "sabotaging" the nation.

The anti-terrorism law allows for detention of up to 28 days.