SINGAPORE - Olympic champion Joseph Schooling and multiple South-east Asian Games gold medallist Amanda Lim are determined to make amends after they were investigated by the Central Narcotics Bureau (CNB) for possible offences related to the consumption of cannabis.

Speaking to the media on the sidelines of the Singapore Red Cross Youth's 70th anniversary celebration on Saturday, Minister for Culture, Community and Youth Edwin Tong said he has spoken to the swimmers and they know they have transgressed.

"They understand the gravity of the situation and they are very determined to make amends and to show that they will rehabilitate. They know it is a mistake, and I think they will come back even stronger," said Mr Tong.

On Tuesday, national sports body Sport Singapore revealed in a statement that the CNB had investigated Schooling, 27, and fellow national swimmer Lim, 29, for the consumption of cannabis.

Schooling, Singapore's only Olympic gold medallist, confessed to taking the drug while he was on short-term disruption from full-time national service in May.

His urine tests for controlled drugs were negative and he has been dealt with by the Ministry of Defence. Schooling has been placed on a Singapore Armed Forces-supervised urine test regime as part of the treatment and rehabilitation process.

He was also issued a formal letter of warning, and will no longer be eligible for leave or disruption to train or compete while in NS.

Lim was issued a stern warning by the CNB under the Misuse of Drugs Act.

Mr Tong, who is also Second Minister for Law, said drug consumption is not condoned here, and Singapore has a very strong stance against it.

He added: "But at the same time, I think Singaporeans have displayed a lot of empathy, a lot of support, care and concern for the well-being of the swimmers themselves, who have come out and taken responsibility.

"They now want to rehabilitate. I think we need to give them space for that, and support them on their journey."