Former prime minister Dr Mahathir Mohamad says he is more focused on Bersih's protest against Prime Minister Najib Abdul Razak than the organisation's funding allegedly linked to US billionaire George Soros.

"For now, I am only focusing on the protest against Najib, I am not involved with the group's source of funding," Mahathir is quoted as saying in a Sinar Harian report.

He added that the Soros-linked funding allegation is aimed at scuttling the Bersih 5 rally on Nov 19.