Washington can continue wiretapping without warrants until its appeal against a ban on the practice is heard, a US federal appeals court has ruled.
President Bush says the taps are a much-needed device
Under the scheme, approved by President Bush after the 11 September attacks in 2001, the monitoring of phone calls and e-mails to and from the US is allowed.
In August, a federal judge ruled it was unconstitutional and must be halted.
The case was brought by civil liberties campaigners, but the government appealed against the ruling.
The 6th US Circuit Court of Appeals in Cincinnati, Ohio, on Wednesday suspended Judge Anna Diggs Taylor's order that the programme be stopped.
In a three-paragraph ruling, the court said Judge Taylor's order would be stayed based on factors including the chances of the government winning on appeal and the public interest.
The Bush administration welcomed the ruling.
"We are pleased to see that it will be allowed to continue while the Court of Appeals examines the trial court's decision, with which we strongly disagree," deputy White House press secretary Dana Perino said in a statement.
Mr Bush authorised the Terrorist Surveillance Programme, as the secret interception scheme is known, after the 11 September terror attacks in 2001.
The White House has said the scheme is legal and is needed in what Mr Bush describes as the war on terror.
It allows the monitoring of international phone calls and other electronic communications to or from the US involving people the government suspects have terrorist links.
But after the programme was uncovered by the media a year ago, the American Civil Liberties Union (ACLU) filed a lawsuit arguing that the scheme was unconstitutional.
In her ruling on 17 August, Judge Taylor said the surveillance programme violated protections on free speech and privacy.
The US government appealed against the ban. A ruling is not likely to be delivered before the end of the year.