Najib spoke softly as he entered his plea in the High Court on Wednesday.
Lawyer Tan Sri Muhammad Shafee Abdullah, who represented Najib, said it would be better if the prosecution applied for yesterday's case to be combined with the three charges of CBT and one of abuse of power with regard to RM42 million funds belonging to SRC International faced by his client earlier.
Appearing at a court in Kuala Lumpur, Najib was charged with three counts of money-laundering over claims he pocketed 42 million ringgit (342 million baht) from a former unit of scandal-hit sovereign wealth fund 1MDB.
In a packed courtroom, the three new charges were read out to Mr Najib.
According to an investigation by the Wall Street Journal, about $10 million originating from SRC was transferred to Najib's personal bank accounts, a fraction of the hundreds of millions of dollars from 1MDB that was allegedly funnelled to him.
The money laundering offence carries a penalty of a jail term of up to 15 years and a fine of not less than 5 times the value of the proceeds of any illegal transfers, or five million ringgit, whichever is the higher.
Don't miss out on the latest news and information.
Prime Minister Mahathir Mohamad campaigned during the 14th General Elections in Malaysia in May on the basis of "catching Dato Seri Najib Razak" who was then accused of syphoning billions from the 1mdb.
Reopening the investigations into 1MDB after Najib lost power, Malaysian anti-graft officers have revealed how their earlier investigations were obstructed by Najib's government.
He pleaded not guilty to those charges.
Tan Sri Irwan was removed from his post and that of 1MDB chairman after Najib was ousted.
SRC has been the initial focus of Malaysian investigators as all the suspicious transactions involving it went through Malaysian entities, unlike other 1MDB-related transactions that went through foreign banks and companies. Malaysian financier Low Taek Jho (better known as Jho Low) allegedly bought the yacht using funds stolen from 1MDB.
The US Justice Department, which is seeking to recover items allegedly bought with stolen 1MDB cash in America, estimates that United States dollars 4.5 billion in total was looted from 1MDB.