If you're thinking of donating money to help Malaysia's former Prime Minister Najib Razak, who was charged with 21 counts of money laundering and four counts of abuse of power on Thursday (Sept 20), don't. At least for now.

An appeal for donations to raise RM3.5 million (S$1.16 million) to bail Najib out of jail which has been making the rounds on social media is bogus, Najib said on Facebook late on Thursday.

He denied making any request on social media to raise RM3.5 million for his bail, and warned the public not to fall for the hoax.

"I thank you brothers and sisters for your support and your willingness to help me. However, I want to make it clear that I never asked any party for donations," he said, noting that he had been allowed to return home pending full payment of his bail by next Friday (Sept 28).

Najib said he would raise the money by using the balance of a sum raised in July - when he was slapped with seven charges of criminal breach of trust, bribery and money laundering before being released on RM1 million bail - and with the help from his family and friends.

On Friday (Sept 21) the 65-year-old posted RM1 million of the RM3.5 million bail at the Kuala Lumpur Court.

But he did not discount the likelihood that he may need to canvass donations.

"If there is a need to get the support from the public to raise funds for bail or legal fees, the account details will be posted on my official site here," the one-time premier wrote on Facebook.

Najib now faces a total of 32 charges over missing funds linked to 1Malaysia Development Berhad (1MDB), a state fund which he founded and chaired. He denies all of them.

The case is next set for court mention on Nov 16.