KUALA LUMPUR - There is little choice for Malaysian Prime Minister Najib Razak but to sue for defamation now that The Wall Street Journal (WSJ) has stood by its report that US$700 million (S$955 million) from state investor 1Malaysia Development Berhad (1MDB) was found in his personal bank accounts, lawyers said.

A delay in Najib's move to seek legal recourse would be seen as if the newspaper had been accurate in its July 2 and July 6 reports, which it said were based on documents sourced from investigators, the Malaysian Insider reported on Thursday.

The news portal quoted lawyers as saying that Najib could file the suit in Malaysia or elsewhere where the report was published.

The website quoted lawyer Datuk Bastian Pius Vendargon as saying that Najib's next step is to name the journalist and publisher, Dow Jones & Company, as defendants to kickstart his civil action for loss of reputation.

"I don't think it is necessary for Najib's lawyers to send a notice of demand to ask the publisher to retract the report and ask for an apology since they are firm on their stand," he said.

He added that Najib was left with no choice but to file the suit or the WSJ reports would be taken as the truth.

"Public perception will be that the report is true if no lawsuit is initiated immediately," he was quoted as saying.

Najib's lawyers had sent a legal letter on July 8 seeking clarification from WSJ and Dow Jones as to whether their report meant that Najib had misappropriated funds. WSJ has replied to the letter but the contents are not known, the Malaysian Insider said.

However the newspaper has twice stated publicly that it stands by its report, according to the news portal.

Najib's lawyer Wan Azmir Wan Majid told Malaysian Insider on Wednesday night that they would study WSJ's reply to their letter and advise the prime minister on the next course of action.

In its reports, the WSJ alleged that US$700 million (S$960 million) had been moved from 1MDB into Mr Najib's personal bank accounts.The prime minister has denied taking 1MDB funds for personal gain, but he has not directly addressed the allegations of the fund transfers into his accounts.

These allegations are being investigated by the special task force that has been set up to probe alleged irregularities at 1MDB.