A US federal appeals court on Friday overturned an earlier ruling by a lower court against the federal government's controversial bulk collection of Americans' phone data.

The ruling by the US Court of Appeals for the district of Columbia circuit said the previous ruling by the lower court in Washington, D.C., which declared that bulk metadata collection programme of the National Security Agency (NSA) was unconstitutional, had no sufficient grounds, Xinhua reported.

After Friday's ruling, the massive metadata collection programme, first disclosed by NSA whistleblower Edward Snowden in 2013, would continue its operation till it expires at the end of November.

White House spokesman Josh Earnest on Friday called the ruling "consistent with what this administration has said for some time, which is that we did believe that these capabilities were constitutional".

Larry Klayman, a lawyer who sued the NSA over its domestic surveillance programme, said he would appeal to the Supreme Court.

In June, the Congress passed a reform bill to phase out the NSA's phone surveillance programme by the end of November and replace it with a new system that, though continuing to require the private companies to keep phone records of millions of Americans, would limit the federal government's access to those phone records.

With IANS