The US has charged three British men with terrorism offences over alleged surveillance of major financial centres in New York, Newark and Washington.
The alleged plot prompted extra security in New York
The three men are already in custody in the UK, facing similar charges.
Dhiren Barot, 32, Qaisar Shaffi, 25, and Nadeem Tarmohammed, 26, all of Willesden, north-west London, were arrested in August 2004.
US charges that they plotted chemical or radioactive attacks on the buildings carry possible life sentences.
US Deputy Attorney General Jim Comey indicated that the US would seek to extradite the three men, who are due to face trial in the UK early next year.
But any extradition application would only be made after the completion of UK legal proceedings and possible sentences, Mr Comey added.
The three men were arrested in London as part of a series of co-ordinated anti-terror raids by police forces across the UK.
Five other men who were arrested and charged alongside Mr Barot, Mr Shaffi and Mr Tarmohammed were not included in the US indictment.
The US Department of Justice unsealed an indictment containing charges broadly similar to those levelled against the three men in the UK.
The three are accused of carrying out surveillance of the New York Stock Exchange and Citigroup buildings in New York, and the headquarters of the World Bank and International Monetary Fund in Washington.
The Prudential Plaza in Newark, New Jersey was also allegedly kept under surveillance.
All three men have already been charged in the UK with conspiracy to commit a public nuisance by the use of radioactive materials, toxic gases, chemicals and/or explosives.
Mr Barot and Mr Tarmohammed are alleged to have been found in possession of reconnaissance plans of the buildings.
Mr Shaffi is accused of possessing an extract of the Terrorist's Handbook, detailing methods of preparing chemicals and explosive devices.
The discovery of the alleged plot prompted US authorities to dramatically increase security around the buildings.
Armed guards and anti-terror troops were dispatched to the streets of New York's financial district.