A terrorist cell with alleged links to al-Qaida planned to blow up pubs, nightclubs and trains in a bombing campaign in the UK, the Old Bailey heard.

Some members of the seven- strong gang, which included four men from Crawley, had trained at terror camps in Pakistan where they hatched the plot after practising causing explosions with ammonium nitrate and aluminium powder, it was alleged.

The plot to kill and maim is said to have involved 600kg of ammonium nitrate fertiliser and the cell, all British citizens, planned to smuggle detonators into the UK through Belgium hidden in small radios, the court heard.

David Waters QC, prosecuting, said two of the alleged plotters claimed to be working for al-Qaida's "number three".

He said: "Most of the necessary components were in place and all that remained before their plans achieved their ultimate goal was for the target or targets to be finally agreed."

One of the defendants, Waheed Mahmood, had been working for National Grid Transco which was "of significance in this case", Mr Waters said.

The company operates the high voltage electricity system in England and Wales and the high pressure gas system in Britain.

The aim of the plot was "at the very least to destroy strategic plant within the UK or more realistically to kill and injure citizens of the UK", Mr Waters said.

A great deal of preparation had been done in Pakistan but the targets were to be in the UK, he said.

In July 2003, members of the group travelled to a training camp in Kalam posing as tourists visiting lakes and glaciers, even taking photographs of themselves.

At the camp, they carried out a successful explosion using between 0.5kg and 1kg of ammonium nitrate and aluminium powder and making a U-shaped hole under the ground.

They also used false names in Pakistan, the court heard. One of the defendants used the name Hamza and codes were used in emails, including referring to detonators as "cigarettes".

Omar Khyam, 24, from Crawley, was said to be at the centre of operations.

The other defendants are his brother Shujah Mahmood, 19, Waheed Mahmood, 34, and Jawad Akbar, 22, all from Crawley, Anthony Garcia, 23, of Ilford, east London, Nabeel Hussain, 20, of Horley, near Gatwick, who was a student at Brunel University, and Salahuddin Amin, 31, from Luton.

They deny conspiring to cause xplosions between January 1, 2003, and March 31, 2004.

Khyam, Garcia and Hussain also deny a charge under the Terrorism Act 2000 of possessing an article for terrorism - the 600kg of ammonium nitrate fertiliser.

Brothers Omar Khyam and Shuja Mahmood also deny having aluminium powder for terrorism.

Canadian Mohammed Momin Khawaja is awaiting trial there over the plot.

Another alleged member of the cell, Mohammed Babar, a Pakistani-born American citizen who has pleaded guilty in New York to a role in the "British bomb plot", is expected to give evidence against the British defendants.

He met the group he referred to as the "Crawley lot" when he travelled to England to raise money for the Jihad in Afghanistan in November 2002.

Omar Khyam told him they were working for Abdul Hadi, who he said was al-Qaida's "number 3", the court heard.

In June 2003 in Pakistan, Khyam told Babar he wanted to "do operations" in the UK because it was "unscathed and needed to be hit because of its support for the US", prosecutor David Waters said.

"He then referred to potential targets - pubs, nightclubs or trains."

Shujah Mahmood is said to have gone to Pakistan from the UK with digital scales to measure explosive ingredients.

The only defendant who was not known to Babar was Hussain, Mr Waters said.

Babar had met Waheed Mahmood, who was "a supporter of al-Qaida", in Pakistan in 2001.

Mr Waters said: "Waheed said he couldn't understand why people were coming all the way to Pakistan or Afghanistan to fight when they should be fighting Jihad in the UK and conducting operations there."

The trial continues.