A terror plot to blow up seven airliners with bottle bombs was almost ready for action and would have caused civilian deaths on an 'unprecedented scale', a court was told.

Eight British men are accused of planning co-ordinated mid-air attacks on flights out of London's [Images] Heathrow airport to the US and Canada [Images].

Prosecutor Peter Wright, QC, told the Woolwich Crown Court on Thursday that the atrocity would have had 'a truly global impact'. The trial is expected to last up to eight months.

Wright said they had planned, 'all in the name of Islam', to carry out a 'series of coordinated and deadly explosions' and were 'indifferent to the carnage' that would have been caused.

All the seven flights allegedly targeted could carry between 241 and 285 passengers.

They were to cities, including Chicago, San Francisco, Toronto, Washington, JFK in New York and Montreal. They all left Heathrow daily within roughly two and a half hours of each other.

The eight, including seven from London, were flanked by security guards at the start of what has been described as the world's biggest terror trial. All deny conspiracy to murder and conspiring to commit an act of violence likely to endanger the safety of an aircraft.

They are: Abdulla Ahmed Ali, Assad Sarwar, Tanvir Hussain, and Ibrahim Savant, all aged 27, Mohammed Gulzar [Images] and Arafat Waheed Khan, 26, Waheed Zaman, 23 and Umar Islam, also known as Brian Young, 29.

Wright named the ringleaders as Ali, Sarwar and Gulzar and said Ali was one of those prepared to blow themselves up on a jet.

However, during conversations monitored by police the conspirators talked about as many as 18 suicide bombers at different airport terminals.

"At the very least, seven planes would have been targeted," Wright said.

At the time of their arrests they were 'almost ready' to put their plan into action and some were prepared to lose their lives with 'the cold eyed certainty of a fanatic'.

The arrests in the summer of 2006 led to a huge security crackdown at British airports, with passengers being banned from taking liquids on planes.

The jury heard that the gang planned to smuggle components of the homemade bombs on to the flights as 'innocuous hand luggage'.

The court heard the bombers intended to use hydrogen peroxide and mix it with a product called Tang, used in soft drinks, to turn it into an explosive.

They intended to carry it on board disguised as 500ml bottles of Oasis or Lucozade by using food dye to recreate the drinks' distinctive colour.

The detonator would have been disguised as AA 1.5 batteries. The contents of the batteries would have been removed and electric element such as a light bulb or wiring would have been inserted. A disposable camera would have provided a power source.

"These items would have the capability of being detonated with devastating consequences," said Wright.

Britain has seen a string of major cases involving bombings in recent months.