U2 played to 50,000 people at the QSAC Stadium

Bono made the plea as he sang Sunday Bloody Sunday at the Brisbane gig.

He asked that David Hicks, who has been held at the US military prison without trial for five years, be sent home to be tried "fairly".

"In our twenties, we used to do a lot of work for Amnesty and tonight we're still working for them," he said.

Mr Hicks, 31, has pleaded not guilty to charges of attempted murder, conspiracy to commit war crimes and aiding the enemy.

The US Supreme Court overturned those charges though in June after ruling that the military tribunals were illegal.

No promises

In the past the Australian prime minister, John Howard, has refused to intervene in getting Mr Hicks sent home.

He has, however, agreed to meet with Bono over the matter but will not be drawn on any conditions that may be set.

"I don't commit in advance to businessmen in this country, and I don't certainly don't do it to high grade Irish entertainers," he said.

According to government ministers, the Pentagon has promised Mr Hicks will be among the first terror suspects to be tried by the new tribunals.

Amnesty International has already labelled them as unfair.