The Bush administration on Friday remained tightlipped on the role played by US intelligence agencies in busting the suspected Al Qaeda [Images] plot to blow up several airliners over the Atlantic and its Pakistani links.

Washington also refused to comment on media reports that pressure was applied on Islamabad to make a "key arrest" that eventually led to a number of arrests in Britian.

"One of the things that we're doing, of course, is we're cooperating with the British authorities, and they're the lead in the investigation and subsequent prosecution and I don't want to say anything that might in any ways adversely affect the ongoning investigation. I'll wait for the British authorities to get that information out to the public," US Attorney General Alberto Gonzales said in a TV interview.

The nation's top law enforcement officer also refused to confirm or deny a report that pressure was brought on Pakistan to make a key arrest that led to nabbing of suspects in the United Kingdom.

Elaborating on the co-operation between the US and British intelligence agencies, Gonzales said, "There were information, tips and leads within the US that the FBI, the Department of Justice, other law enforcement and intelligence agencies followed up on. The FBI had over 20 agents running down each of these leads."

"It is true, after doing all of that work, we don't believe, based on what we know, that there is an ongoing plot here in the US, but we shared everything that we learned about this plot with the British authorities. And we believe that our efforts were important, certainly instrumental in disrupting this current threat." he added.      

The top Justice Department official did not comment on the role played by the Patriot Act or the National Security Agency's surveillance programme.

"We want to be careful about how much we disclose at the initial stages of this investigation. We don't want to jeopardise the subsequent prosecution, not only in the UK but perhaps here in the United States.

"The president of the United States expects that all of us working in government utilise all the tools available to us under the Constitution and our laws to disrupt these kinds of attacks and to prosecute, to bring to justice people engaged in criminal activity against the United States," he said.

"We have a responsibility in government to ensure that we're taking advantage of changing technology ourselves. We shouldn't handicap ourselves. Obviously, we are bound by the Constitution and by our laws, but we should take advantage of the technologies that currently exist, that allow us to engage in meaningful surveillance of the enemy, particularly during a time of war," the attorney general remarked.

Both the State Department and the White House have also been careful in commenting on the fact that most of the suspects arrested in Britain were of Pakistani origin.

They also remained tightlipped on any positive role played by Islamabad in the plot that would have seen at least nine American airliners blown up over the Atlantic.