John Howard (file photo)

Australia has ruled out taking Singapore to the International Court of Justice to stop its planned execution of an Australian drug smuggler. Australian Prime Minister John Howard says such a move could be counterproductive in the faltering bid to save the life of 25-year-old Van Nguyen.

Prime Minister Howard says trying to force Singapore to have the case heard by the International Court of Justice - known as the ICJ - could damage Van Nguyen's slim chances of avoiding the gallows.

Singapore, whose laws provide for a mandatory death sentence in serious drug cases, plans to hang the 25-year-old Vietnamese-born Australian in nine days.

Mr. Howard, on a visit to Afghanistan and Pakistan, said the ICJ had no jurisdiction in the case, as Singapore was doing nothing illegal.

The prime minister also says he is unwilling to resort to trade or diplomatic sanctions against Singapore.

"As an instrument of policy, I certainly am opposed to saying, 'Well, because the Singaporean government is going ahead with this execution, we are going to take such and such a position on a trade issue.' That is not sensible, and it's not going to serve any good purpose," he said.

Mr. Howard has met with the condemned man's family, but has told them his government could do nothing to help.

Van Nguyen was caught trafficking 400 grams of heroin from Cambodia to Australia via Singapore in 2002.

He told the police he was smuggling the drugs to help pay off his twin brother's debts.

Australia has repeatedly pleaded for his life to be spared, on the grounds that he has no previous criminal convictions. Canberra has also argued that he could help with investigations into drug syndicates if he were allowed to live.

Van Nguyen's lawyer, Lex Lasry, says Singapore has commuted death sentences in the past, and he is not giving up hope.

"They've done it, but they've never done it as late in the piece as this, I would accept that. So that obviously has some bearing on our present circumstance, but it's not too late to persuade them that they're making the wrong decision," he said.

The Australian government, however, has conceded that it is highly unlikely Singapore will change its mind.

If his death sentence is carried out next week, Van Nguyen will become the first Australian to be executed overseas in more than a decade. Australia does not have the death penalty.