The London-based architect will design Tower Two as part of Daniel Libeskind's masterplan for the former World Trade Centre site ( pictured).
The project will include 240,000m 2of office space and approximately 13,000m 2of retail space, both at street level and as part of an underground concourse linking to a new transportation hub.
The commission comes two years after Foster was widely tipped to take on the design of Freedom Tower before Libeskind won the international competition.
New York's governor George Pataki said yesterday afternoon at a press conference that he believed the appointment of Foster reflected all that has happened since the terrorist attack.
'The World Trade Centre had a long history as an international centre of commerce, and after 9/11 there was a global outpouring of support and solidarity,' he said.
'It is only fitting that one of the international community's most esteemed architects should be chosen to join an already illustrious and international group of men and women working to rebuild and revitalise Lower Manhattan.
'The selection of Norman Foster to design Tower Two is just the latest signal that the rebuilding of the World Trade Centre site is moving forward in achieving its destiny as a world-class central business district.
'We look forward to seeing his vision for the tower and to commencing construction on the remaining signature projects - the Freedom Tower and Reflecting Absence, the memorial to our nearly 3,000 lost heroes, this spring,' he added.