Shanmugam travelled from Sydney to Adelaide, where he was arrested at the airport on Feb 21 while attempting to board a flight to Malaysia.
He initially appeared in Adelaide Magistrates Court on Monday before he was extradited to New South Wales to face charges.
The seized methamphetamine has an estimated street value of A$29.6 million (US$18.8 million) while the cocaine was thought to be worth A$2.6 million.
The offences carry a maximum penalty of life imprisonment.
In response to CNA’s queries, Singapore’s Central Narcotics Bureau (CNB) said it was aware of reports that a 55-year-old Singaporean man had been arrested in Australia for suspected drug-related offences.
“CNB will render the required assistance to our counterparts in Australia to aid their investigation. As their investigation is ongoing, it is inappropriate to comment further at this point in time,” said a spokesperson.
