A federal appeals court in New York has rejected the American Civil Liberties Union's effort to stop bulk collection of its phone records while a more limited collection system is put in place.

The 2nd U.S. Circuit Court of Appeals said Thursday that Congress intended for data collection to continue during a six-month transition period before a new law takes effect. Earlier this year, the appeals court in Manhattan struck down the government's mass collection of Americans' phone records, finding Congress never authorized it.

Congress then approved a more limited collection method due to take effect Nov. 29.

The 2nd Circuit says an abrupt end to the current program would harm the public interest in surveilling terrorist threats.

An ACLU lawyer says the civil rights group disagrees with the ruling.