Though the Department of International Relations and Cooperation could not say how many South Africans were currently held in Singaporean prisons for drug-related crimes, it is believed to be nearly a dozen.

In May, Johannesburg restaurant manager Brett Theo Savage was sentenced to life in prison for smuggling nearly 3kg of crystal methamphetamine into Bali.

He was arrested in October 2011 at Ngurah Rai International Airport, having departed from Johannesburg.

Savage, 44, was sentenced a week after 38-year-old Sheilla Motsweneng was sentenced to 15 years for trafficking 2.5kg of crystal methamphetamine. She, too, was arrested in October 2011 at Ngurah Rai International.

Singapore's deputy prime minister yesterday said the country planned to relax its laws so that the death penalty was not mandatory.

Amnesty International and other rights groups say the wealthy southeast Asian city-state - which has a zero-tolerance policy towards illegal drugs and imposes long jail terms on convicted users - has hanged hundreds of people, including dozens of foreigners, for narcotics offences in the past two decades.

Department of International Relations and Cooperation spokesman Clayson Monyela yesterday refused to comment.

Jacob van Garderen, of South Africa's Lawyers for Human Rights, said his group welcomed Singapore's move.

"We have been agitating for the abolition of the death penalty not only in South Africa [when the law was in effect] but also in other countries.

"We hope this is the first step in the complete abolition of the death penalty," he said.

Singaporean Deputy Prime Minister Teo Chee Hean told his country's parliament that the government, having reflected on changes in "our society's norms and expectations", will propose by the end of the year giving judges more leeway in dealing with certain drug and murder cases.

"Though there is a broad acceptance that we should be tough on drugs and crime, there is also an increased expectation that, when appropriate, more sentencing discretion be vested in the courts."

Singapore, whose customs forms warn arriving travellers of "death for drug traffickers", has suspended all executions since the government began a review of capital punishment a year ago.

Drug offenders make up almost two-thirds of Singaporeans in prison, said Hean.