Ten of the 11 defendants were present at the hearing where they were formally charged on Monday. All are Yemenis and at least six were born in Saudi Arabia.

The charges also include possession of arms and explosives and forging documents and passports.

A public prosecutor said the 11 had trained in camps in Afghanistan between 1998 and 2002 and were plotting and raising funds for "criminal acts" inside Yemen and abroad.

The prosecutor also charged that the men had planned to travel to Iraq to fight US-led forces there.

He demanded the maximum punishment of between seven and 10 years in prison.

Charges denied

Some of the accused denied the accusations, although a number of them admitted to forging documents.

Aged between 24 and 43, the 10 present were named as Muhammad al-Kadhmi, Abd Allah al-Wadai, Mansur al-Bihani, Shafiq Ahmad Umar, Ibrahim al-Muqri, Muhammad Hatim, Saddam Ismail, Faris al-Wadai, Abd al-Rauf Nasib and Ahmad Muhammad al-Qardai.

The eleventh defendant, Faris al-Nahdi, did not attend the hearing, which was adjourned until 21 February.

Six of the men were arrested in Saudi, two in Syria and the rest in Yemen.

Verdict pending

Yemen, which has cracked down on suspected al-Qaida members at the behest of the US, has already tried and convicted two groups.

One was for the 2000 bombing of the US navy destroyer Cole in Aden which killed 17 American sailors and the other for the bombing of a French tanker, the Limburg, two years later.

On 5 February, the appeals court in Sanaa upheld the death sentence against a Yemeni and sentenced to death another who had been jailed over the bombing of the Limburg and other attacks.

The appeals court will deliver the verdict in the Cole case on 26 February.