Four men have admitted to a plot to blow up the London Stock Exchange right in the heart of the capital.

Mohammed Chowdhury, 21, Shah Rahman, 28, Gurukanth Desai, 30, and Abdul Miah, 25 pleaded guilty at Woolwich Crown Court to engaging in conduct in preparation for acts of terrorism.

Five other men pleaded guilty to various lesser terror offences.

One defendant had a handwritten list of names and addresses including of London Mayor Boris Johnson, the US Embassy, and the London Stock Exchange.

They were arrested as part of a huge anti-terror operation in London, Cardiff, and Stoke-on-Trent.

Those plotters also wanted to send out five letter bombs before Christmas 2010.

Prosecutors said the plans were akin to a "Mumbai-style" terror attack.

The nine defendants were accused of agreeing on targets, discussing materials and methods, and researching files "containing practical instruction for a terrorist attack", according to AP.

None were from the notorious terrorist group al-Qaida, but they did follow the preaching of radical Yemeni cleric Anwar al Awlaki, killed by a US drone strike in 2011.

They will be sentenced next week.