Defence Minister Hishammuddin Hussein has demanded proof over claims that Prime Minister Najib Abdul Razak and his government have been bought over by Saudi Arabia.

"They can accuse but if it is true that we've been bought over, prove it. No proof, no talk," he told journalists in Kuala Lumpur today.

"Political 'spins' (such as this) are accusations that change with the season [...] it's all polemics.

"What's important is we want to know the truth and look forward," he added.

Hishammuddin, who is also Najib’s cousin, was responding to Amanah president Mohamad Sabu who claimed that the prime minister and his government have been bought over by the Arabs.

This is after Saudi Arabia Foreign Minister Adel al-Jubeir said he was aware of the political donation given to Najib and that it was given without expecting anything in return.

Najib had repeatedly claimed the billions of ringgit in his personal account was a political donation from Saudi Arabia.

Attorney-general Mohamed Apandi Ali has also cleared him of any wrongdoing with regard to receiving RM2.6 billion in donations reportedly from the Arabs.

The prime minister and his supporters have accused detractors, namely Dr Mahathir Mohamad, of harping on the issue with aim of toppling Najib from power.