Abdulla Ahmed Ali, 27, Assad Sarwar, 28, and Tanvir Hussain, 27, admitted the offence at Woolwich Crown Court, in south east London. The men also admitted conspiring to cause public nuisance by distributing videos threatening suicide bomb attacks in Britain.

Two of their co-defendants, Ibrahim Savant, 27, and Umar Islam, 30, also admitted conspiring to cause a public nuisance.

A jury must still decide if the five men, and three others, are guilty of conspiring to murder thousands in a wave of mid-air terrorist explosions using homemade liquid bombs.

The charges the men face have been amended. All eight men deny two charges of conspiracy to murder between January 1 and August 11 2006. One of the charges specifies that the attacks would involve the detonation of improvised bombs on passenger aircraft.

Prosecutors claim the eight men plotted to blow up passenger jets flying from Heathrow to major cities in North America.

They planned to use powerful hydrogen peroxide liquid bombs disguised as soft drinks to bypass airport security, jurors were told. The devices would be assembled by injecting the chemicals into plastic soft drinks bottles and detonated using a battery from a camera flash, it was claimed.

They were being assembled at a bomb factory flat bought by the gang for cash in Forest Road, Walthamstow, north east London, the court heard. The same flat was used by six members of the gang to record martyrdom videos in which they ranted hatred against the West and non-Muslims, jurors were told.

The defendants are Ali, of Prospect Hill, Walthamstow, east London; Sarwar, 28, of Walton Drive, High Wycombe, Bucks; Hussain, 27, of Nottingham Road, Leyton, east London; Mohammed Gulzar, 26, of Priory Road, Barking, east London; Savant, 27, of Denver Road, Stoke Newington, north London, Arafat Waheed Khan, 27, of Farnan Avenue, Walthamstow; Waheed Zaman, 24, of Queen's Road, Walthamstow; and Islam, aka Brian Young, 30, of Bushey Road, Plaistow, east London.

The jury is expected to retire next week.