Rebuilding Ground Zero

A hastily arranged ceremony marked the official start of rebuilding at Ground Zero yesterday morning after months of tense negotiations cast doubt over the project.

New York's mayor, Michael Bloomberg, the state governor, George Pataki, and developer Larry Silverstein met builders at the site to inaugurate work on the Freedom Tower, one day after announcing that they had finally thrashed out an agreement.

The talks had centred on whether Mr Silverstein - who bought the lease to the World Trade Centre seven weeks before it was destroyed - had the resources to meet his commitments. The new deal hands control of the lease to the Port Authority of New York and New Jersey.

The entire project, involving four other skyscrapers, will provide about 820,000 square metres (8.8m square feet) of office space at an estimated cost of $6.3bn (£3.5bn), and is expected to be finished by 2012, though a memorial should be in place by 2009. "There are some issues that need to be resolved", Mr Silverstein said, "but my focus, like that of all New Yorkers, is on getting the Freedom Tower under way."

Not quite all New Yorkers agree, though. The Freedom Tower "should be the last building to be done, and should be built more modestly", said Susan Fainstein, a professor of urban planning at Columbia University. "First, because it's such an obvious target, and secondly, in order to harden it as a target, it's become an architectural monstrosity."

No private firms have committed to taking space in the tower. The Port Authority has guaranteed that about half of the available floors will be occupied by government agencies.