Amid the raging debate over the RM2.6 billion donation in Prime Minister Najib Abdul Razak's bank accounts, a blog has targetted business tycoons close to Dr Mahathir Mohamad.

The pro-Najib administration MyKMU.net published an open letter addressed to the former premier on this matter with a photograph showing Berjaya Group's Vincent Tan together with Mahathir and former deputy premier Muhyiddin Yassin.

The writer was identified as Amin Yatim from Petaling Jaya. No other details were available.

Posing a question to Mahathir, the letter writer asked if it was true Berjaya Group's Tan contributed close to RM400 million to Pakatan Rakyat in the 2013 general election.

Amin described Tan as a "businessman whom Mahathir is fond of and had recently organised the former premier’s (90th) birthday bash ala James Bond."

"Tan, who received special treatment during the BN administration under Tun (Mahathir), is said to have contributed almost RM1 billion to rival parties since 2008.

"You must also know how many hundreds of millions YTL, Syed Mokhtar (al-Bukhary) and other businessmen contributed to Pakatan's coffers in a most tightly contested election in the nation's history," read the letter.

Defending Najib, the letter writer said the prime minister took over the leadership when Umno and BN were weak while their opponents grew tenfold in strength.

"Najib and Tun knew the 2013 general election was no longer a 'David versus Goliath' bout.

"On the contrary, it was the 'mother of all battles' in the Malaysian context. Najib could no longer depend on business cronies alone... Certainly, Tun understands all this," he added.

Amin also lashed out at Mahathir for attacking Najib on this issue.

"In 2008, when you wanted to topple Pak Lah (Najib's predecessor Abdullah Ahmad Badawi), you (Mahathir) wrote that you handed over RM1.4 billion in cash, assets and shares under your care when serving as Umno president through an official and minister.

"Why wasn't this put into an Umno account? Why a trustee account? Tun knows the answer and the problems.

"Do you (Mahathir) believe that you are the only one with integrity while the others are liars, when the fact is that it was during your era that billions from Umno vanished.

"I am disappointed you are willing to attack Najib who spent to ensure BN's victory but close your eyes to the action of your cronies who contributed to rival parties," he added.

DAP dismisses allegation

Amin also expressed disappointment that Mahathir chose to rain blows on Najib when the latter helped the former premier win the 1987 Umno election.

"What you have done over the past months is very saddening. You are no longer behaving like a statesman, and can no longer be a friend.

"What hurts more is that you can no longer be a good party member like how you asked us to do so when you were prime minister," he added.

Meanwhile, DAP treasurer Fong Kui Lun dismissed the allegation that business magnate Tan had contributed to the party.

"They are talking nonsense," he said when contacted.

Whereas PKR treasurer-general Tan Yee Kew replied: "I can't comment. I have never heard of such a thing."

Malaysiakini is also attempting to contact Berjaya Group for comment.