The Javits Center had been scheduled to fully reopen in 2010 but the completion date has now been put back to 2013.
Speaking in London during the World Travel Market, NYC & Company senior vice-president Fred Dixon said the provision of a temporary 10,200sqm event space near the Javits site, coupled with the availability of the Piers 92/94 facility in Manhattan, were compensating for the centre's limited capacity while work is underway.
Dixon said: "We are fortunate to have so much space in New York for a range of group sizes and we've also had tremendous hotel development."
New York is also increasing its hotel stock to around 90,000 rooms, with 9,000 added this year and another 9,000 due to come on stream in 2010.
Dixon said these would help the city achieve its 2012 target of attracting 50 million visitors a year, a third of whom will be business travellers.
"The tendency has been down somewhat, as it has in most global destinations, but I think 2010 will be better," he said. "We're seeing a lot of optimism in London this week."
The Javits development will add 7,400sqm of exhibition space, plus new reception areas and an outdoor plaza for open-air functions.