NEW YORK: A former Goldman Sachs partner testified on Wednesday that he and a colleague became "heroes" at the bank for bringing in billions in business from Malaysia's 1MDB sovereign wealth fund, deals he said were cemented through bribes and kickbacks.

Tim Leissner, the former chief of Goldman's Southeast Asia operation, is a star witness in the criminal trial of Roger Ng, the bank's former head of investment banking in Malaysia.

Prosecutors have accused Ng, 49, of receiving millions of dollars in kickbacks for helping embezzle funds from 1MDB. Ng has pleaded not guilty to conspiring to launder money and to violate an anti-bribery law.

Leissner, 52, in 2018 pleaded guilty to similar charges and agreed to cooperate with the government's investigation.

Leissner told jurors on Wednesday in Brooklyn federal court that Ng was Goldman's lead banker on 1MDB and had cultivated a relationship with Malaysian financier Jho Low starting in 2008. Leissner testified that Low was the key decision maker at 1MDB.

Bringing in 1MDB business to Goldman, which ultimately sold $6.5 billion in bonds for the fund and reaped $600 million in fees, "instantaneously made us heroes" within the bank, Leissner said.

Ng's defense lawyer, Marc Agnifilo, said in his opening statement that Ng had no role in the scheme allegedly perpetrated by Leissner and Low.

U.S. prosecutors say Goldman $4.5 billion of the funds raised from the deals was diverted. The bank in 2020 paid a nearly $3 billion fine and arranged for its Malaysian unit to plead guilty in U.S. court.

Under questioning by Assistant U.S. Attorney Drew Rolle, the Germany-born Leissner said he conspired with Ng, Low and others to embezzle some of the funds Goldman raised for 1MDB, use some of the money to bribe officials to win business for the bank, and keep some for themselves.

"The bribes and kickbacks made the transactions possible," he testified. He said he hid the money through offshore shell companies to avoid raising red flags with banks.

"Had we told any bank the truth, this wouldn't have worked," Leissner said.

Prosecutors have acknowledged that Leissner, who has not yet been sentenced, will receive a lighter punishment as a result of his cooperation, but said Leissner's testimony will be backed up by other evidence.

Agnifilo has countered that Leissner lied to prosecutors about Ng's involvement. He spent much of his opening statement attacking Leissner's credibility, portraying him as a socialite who stole to finance a lavish lifestyle.

A lawyer for Leissner declined to comment.

Low, the accused mastermind behind the scheme, was indicted in the United States alongside Ng in 2018. He has not been arrested by U.S. or Malaysian authorities. Low's U.S. lawyer did not respond to a request for comment.