London (CNN) -- Claims that a UK intelligence agency made use of an American mass surveillance program to illegally spy on UK citizens are "unfounded," a parliamentary committee said Wednesday.
The allegations against the UK equivalent of the U.S. National Security Agency were made in a number of media stories after the leak of documents by American intelligence leaker Edward Snowden.
It was said that the Government Communications Headquarters, known as GCHQ, was circumventing UK law by using the NSA's PRISM program to access the content of private communications.
But the parliamentary Intelligence and Security Committee, which oversees the work of UK intelligence agencies, said there is no basis for this claim.
"From the evidence we have seen, we have concluded that this is unfounded," it said in a written statement.
"We have reviewed the reports that GCHQ produced on the basis of intelligence sought from the US, and we are satisfied that they conformed with GCHQ's statutory duties."
The allegations were a matter of very serious concern, it said, because, if true, they would constitute a "serious violation of the rights of UK citizens."
According to the statement, the nine-member committee has taken detailed evidence from GCHQ.
"Our investigation has included scrutiny of GCHQ's access to the content of communications, the legal framework which governs that access, and the arrangements GCHQ has with its overseas counterparts for sharing such information," it said.
Information provided by GCHQ included a list of counterterror operations for which GCHQ was able to obtain intelligence from the United States, as well as a list of all individuals who were being monitored in this way and were in the United Kingdom or believed to be UK nationals, the statement said.
Lawmakers on the committee also discussed the matter with the NSA and U.S. congressional members on a visit to the United States, it said.
However, under the heading "Next steps," the committee said that while GCHQ hadn't circumvented the law, "it is proper to consider whether the current statutory framework governing access to private communications remains adequate."
The panel will examine further the interaction between the various laws governing this area and the policies that underpin their implementation, the statement said.
'Accountability and oversight'
UK Foreign Secretary William Hague welcomed the Intelligence and Security Committee's findings.
"I see daily evidence of the integrity and high standards of the men and women of GCHQ," he said in a prepared statement.
"The Intelligence and Security Committee is a vital part of the strong framework of democratic accountability and oversight governing the use of secret intelligence in the UK. It will continue to have the full cooperation of the government and the security and intelligence agencies."
The GCHQ is one of the three UK intelligence agencies and, according to its website, forms a "crucial part of the UK's national intelligence and security machinery."
Snowden remains in Russia, where he applied for temporary asylum Tuesday from the transit zone in Moscow's Sheremetyevo International Airport. He's been holed up there for the past three weeks because the United States canceled his passport.
Snowden "will leave (the airport) in the next few days because some legal papers are still required to be formalized," Russian lawyer Anatoly Kucherena said Wednesday in Moscow.
"Therefore I think this issue will be resolved within a week and after this the question of granting him temporary asylum will be decided upon."
Meanwhile, Russian President Vladimir Putin told reporters in Moscow that ties between the United States and Russia "are far more important" than any intelligence scandal.
Putin believes that Snowden "never intended to stay here, in Russia, forever."
The asylum claim is the latest step Snowden has made in an attempt to establish a life outside the United States, where he faces espionage charges after publicly admitting that he released documents to the media that exposed U.S. mass surveillance programs.
CNN's Carol Jordan contributed to this report.