Jan. 29, 2010— -- Just months after endorsing the Obama administration's plan to try five high-profile terror suspects in a New York City federal court, top New York officials now say the trial should be held elsewhere -- and that it probably will.
Confronting political reality, the Obama administration is now looking for alternate locations to try alleged 9/11 mastermind Khalid Sheikh Mohammed and four other high-value detainees being held at the Guantanamo Bay detention camp in Cuba.
New York Gov. David Paterson and New York City Mayor Michael Bloomberg said Friday that the anticipated cost of hosting the trials -- and potential unwillingness of Congress to provide federal funds -- could spell economic disaster for the city, which already is facing a massive budget gap.
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"I said it would be phenomenally expensive and it is very disruptive to people who live in the area and businesses in the area," Bloomberg said of his conversations with Obama administration officials. "So the economic impact is detrimental, and nobody knows how big. And it would be better to do it elsewhere if they could find a venue."
Gov. David Paterson echoed Bloomberg's concerns, telling reporters at a press conference on Haiti relief that "we are elated our concerns are being listened to by the president and federal government."
New York City Police Commissioner Raymond Kelley later said that it's "unlikely" the case will go forward in the city at all.
Paterson said he instructed state agencies to assist in the search for alternate venues and will be meeting with the U.S. Marshals Service on Monday.
Federal Funding for NYC Trials in Question
Federal funding for the New York City trials has become a growing concern, White House and Justice Department officials said.
Republicans are almost universally against the idea. Rep. Mike Pence, R-Ind., said today that Republicans will block any funding to try Mohammed in New York City.
"House Republicans last year made an effort to block funding ... but Democrats in Congress prevented us from doing that," Pence said on "Good Morning America" today. "This is a terrible idea to return the mastermind of 9/11 to the scene of the worst terrorist attack in American history -- not only the financial cost but the emotional cost. And frankly, it really compromises the security of that city by making it a terrorist target."
Mayor Bloomberg and U.S. Reps. Nydia Velazquez and Jerrold Nadler -- both Democrats -- have said in recent days that don't believe the trial should take place in New York City. Such powerful voices have taken the White House somewhat by surprise.
"There are places that would be less expensive for the taxpayers and less disruptive for New York City; for example, military bases away from central cities where it is easier to provide security at much less cost," Bloomberg said.
Bloomberg initially supported the idea when it was first announced in November, saying, "It is fitting that 9/11 suspects face justice near the World Trade Center site where so many New Yorkers were murdered."
Bloomberg is not the only one now rejecting the idea. Several Democratic lawmakers who initially backed the plan are also expressing concern.
"This afternoon, I called the White House and told them I thought it would be a very good idea that they look for alternative sites," said Sen. Chuck Schumer, D-N.Y.
Chair of the Senate Intelligence Committee Sen. Dianne Feinstein, D-Calif., sent a letter to Obama today urging him to reconsider holding the trials in New York City. She cited the Christmas day bombing attempt.
"The terrorist threat to the United States remains high," she wrote. "Without getting into classified details, I believe we should view the attempted Christmas Day plot as a continuation, not an end, of plots to strike the United States by al Qaeda and its affiliates."
'New Yorkers Have Been Through Enough'
When the plan to try the terror suspects in New York City was first announced in November, it was met with a lukewarm response.
The Obama administration had put a lot of weight behind the symbolism of trying the suspects at the scene of the crime.
One line of thinking behind trying the suspected terrorists in federal court -- rather than using military commissions -- was that it would send a powerful message to the international community and undo some of the damage the Guantanamo Bay detention camp has done to the U.S. image abroad.
The primary message would be that the United States can use its traditional federal courts to try, convict and execute the people who devised the deadliest terrorist attack ever on U.S. soil, and New York was the "sentimental favorite," as one source said.
New York City officials projected that it would cost $400 million to provide security if the trial of the Sept. 11 suspects took two years. The mayor's office estimated that it would cost another $206 million annually if the trial ran beyond two years, which some say is possible.
Six senators from both parties wrote a letter to Attorney General Eric Holder Tuesday urging him to abandon the idea.
Rep. Peter King, R-N.Y., said Thursday he has introduced a bill that would prohibit the use of Justice Department funds to try Guantanamo detainees in federal civilian courts.
Local officials echoed similar concerns.
"Every time there is a loud noise during the two years of those trials, it's going to frighten people and I think New Yorkers have been through enough," Gov. Paterson said.
The five suspects are Mohammed, Walid Muhammad Salih Mubarek Bin 'Attash, Ramzi Binalshibh, Ali Abdul Aziz Ali and Mustafa Ahmed Adam al Hawsawi.
ABC News' Jake Tapper and the Associated Press contributed to this report.