BBC News - President George W Bush has signed into law a temporary bill allowing the government to eavesdrop on foreign terror suspects without a warrant.
The legislation was approved by the Senate and House of Representatives just before Congress adjourned for the summer recess.
The bill allows taps on foreign phone and internet communications routed via the US, without prior court approval.
President George Bush says the measure is needed to combat terrorist threats.
"When our intelligence professionals have the legal tools to gather information about the intentions of our enemies, America is safer," Mr Bush said on Sunday.
The House voted late on Saturday 227-183 in favour of the bill, which updates the Foreign Intelligence Surveillance Act.
The Senate had voted on Friday.
The new bill gives the government the right to intercept, without warrants, communications between foreigners that are routed through equipment in the US, provided that "foreign intelligence information" is at stake.
It will expire in six months unless Congress renews it. Mr Bush has said he wants deeper, permanent changes.
"We must remember that our work is not done. This bill is a temporary, narrowly focused statue to deal with the most immediate shortcomings in the law," he said.
Despite the vote, many House Democrats expressed strong reservations about the bill, saying it infringed constitutional rights.
"This bill would grant the attorney general the ability to wiretap anybody, any place, any time without court review, without any checks and balances," said Democratic Rep Zoe Lofgren during the debate preceding the vote.
The administration introduced changes to the law after a recent ruling by the Foreign Intelligence Surveillance Court.
That decision barred the government from eavesdropping without warrants on foreign suspects whose messages were being routed through US communications carriers, including internet sites.
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