New York  - The construction of the new World Trade Center in New York is facing financial difficulties, which may delay its completion until at least the middle of 2010, a news reports said Monday.

The Port of Authority of New York and New Jersey, which owns the 16-acre site known as Ground Zero following its destruction by terrorists on September 11, 2001, may have to spend an additional 3 billion dollars to complete the new project, The Wall Street Journal (WSJ) said.

When the project was approved two years ago, the new WTC was expected to cost an estimated 15 billion dollars. WSJ said the exact costs will not be known until government officials and those involved in the construction have calculated the final increased costs.

A spokesman for The Port Authority, Stephen Sigmund, warned against pessimistic predictions. He told WSJ that the Port's top executive director was expected to give "a candid assessment of where we need to go to get the site rebuilt."

"Anyone giving you dates and budgets today would have to have a crystal ball," Sigmund said.

The project was expected to be completed by 2011, the 10th anniversary of the terrorist attacks, which killed more than 2,700 people. The center's 110-storey twin towers collapsed to the ground after being hit by two commercial airplanes hijacked by the terrorists.

The new WTC will feature a 592-metre-tall Freedom Tower, memorials for those killed by the terrorists, a museum, office space and malls. (dpa)