Umno lawyers are in preparing their case against Dow Jones, the publisher of The Wall Street Journal (WSJ), before filing a suit in the United States.
According to Star Online, lawyers are also discussing with New York-based lawyers who specialise in defamation cases.
"We are still preparing the legal work before we send our letters to Dow Jones," a source was quoted as saying.
Last week, WSJ published an explosive allegation that RM2.6 billion of 1MDB funds were transferred into Najib's personal bank accounts.
The prime minister has vehemently denied the claim and blamed former premier Dr Mahathir Mohamad for masterminding this "lie" to oust him.
He described the WSJ report as a continuation of the political sabotage against him and threatened to sue the publication for "criminal defamation".
WSJ has defended its report, citing that it was based on information gathered from Malaysian investigators.
Today, the publication uploaded documents of the purported Najib-1MDB money trail online.
Previously, Attorney-General Abdul Gani Patail confirmed that he had seen the documents relating to the case.
He also said a special multi-agency taskforce had raided companies linked to 1MDB, namely SRC International Sdn Bhd, Gandingan Mentari Sdn Bhd and Ihsan Perdana Sdn Bhd, which were said to have channelled the funds into what is believed to be Najib's personal bank accounts.
Today, the taskforce revealed that it had frozen six bank accounts. Though it did not provide details, Malaysiakini learnt that three of the accounts belonged to Najib.
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