KUALA LUMPUR, Malaysia: In the most significant trial of the multibillion-dollar 1MDB scandal, Malaysia's influential former prime minister Najib Razak was jailed on December 26 for another 15 years and fined US$2.8 billion for abuse of power and money laundering.

Malaysia and U.S. investigators say Najib pilfered at least $4.5 billion from 1Malaysia Development Berhad, a state fund he himself founded in 2009 when he was prime minister.

72-year-old Najib allegedly routed more than $1 billion into his accounts, but claimed he had been made a scapegoat in Malaysia's biggest-ever financial scandal, for which he was imprisoned in 2022.

High court judge Collin Lawrence Sequerah, in his verdict that took five hours to deliver, called Najib's contentions "implausible" and said that people at 1MDB had repeatedly deceived him.

Najib had issued a public apology last year for mishandling the scandal, claiming he was misled by 1MDB officials and fugitive financier Jho Low about the source of the funds in his accounts. Low, who was charged in the United States for his central role in the case, denies wrongdoing, and his whereabouts are unknown.

Najib's lawyer Muhammad Shafee Abdullah said he would appeal the ruling on Monday.

Often called Malaysia's most divisive politician, Najib was found guilty of all four counts of abuse of power and all 21 money laundering charges, after a marathon legal battle that included multiple appeals and a partial royal pardon.

Judge Sequerah said in the verdict that the accused's claim that the charges were a witch hunt and politically motivated was disproved by cold, hard, and incontrovertible evidence showing that he had abused his powerful position in 1MDB, along with the extensive powers vested in him.

Sentences of 15 years for each count of power abuse and 5 years for each money laundering charge were handed down, to be served concurrently, after Najib's current jail term ends in 2028.

Najib was ordered to pay fines of 11.39 billion ringgit ($2.82 billion), and the court said 2.08 billion ringgit in assets must be recovered from him. Failure to deliver on both would result in additional jail time, it said.

Judge Sequerah said that as prime minister, Najib "stood at the very apex of the decision-making process" and evidence revealed he had an "unmistakable bond and connection" with Low, who acted as his proxy and intermediary in 1MDB affairs.

In a statement read by his lawyer, Najib urged Malaysians to remain calm and rational and vowed to continue his fight.

The opulent-living Low and his associates used the siphoned funds to buy a private jet, a $120 million superyacht, hotels, artworks, and jewelry. They also financed the 2013 Hollywood film "The Wolf of Wall Street", U.S. lawsuits have said.

The ruling could fuel further tensions within Prime Minister Anwar Ibrahim's governing alliance, which includes the once-dominant United Malays National Organisation (UMNO), over which Najib retains significant influence even from jail.