Britain won a legal battle which allows its military forces in Iraq to continue detaining a terrorism suspect without charge.

The law lords, sitting as the highest court in England, backed earlier court rulings that the detention of Hilal al-Jedda, 48, who holds both Iraqi and British citizenship, is lawful.

Lawyers for al-Jedda, who has been held in detention since late 2004, had argued his human rights are being breached. But the law lords backed earlier decisions that his detention was in accordance with the United Nations Security Council's mandate.

Rejecting an appeal by al-Jedda's lawyers, Lord Chief Justice Lord Bingham said: "The court of appeal made no error of law."

Al-Jedda came to Britain as an asylum seeker in 1992. He says he returned to Iraq after the fall of Saddam Hussein to see his family and friends and introduce his wife to them. He was originally arrested by US troops on suspicion of being a member of a terrorist organisation. He was then handed over to British troops in Iraq and has since been fighting to be returned to Britain. He denies any link with terrorist groups. His lawyers argue that his detention breaches his right - under the European human rights convention - not to be deprived of his liberty except in accordance with due legal process.

The government argues that he can be held indefinitely because British troops in southern Iraq are part of a UN-backed international force and therefore operate under a UN Security Council mandate, not under European rights law.

The Security Council resolution which backed the international force in Iraq authorises "internment where necessary for imperative reasons of security".