US intelligence agencies have made a fifth attempt to extend their bulk collection of American telephone records – more than a year after the controversial practice was first revealed by National Security Agency whistleblower Edward Snowden.

Despite repeated calls from Congress and President Obama for the mass gathering of private US phone records to be banned, a court has approved the request in secret, allowing the NSA to continue collecting metadata until 12 September 2014.

In a joint statement released late on Friday afternoon, the justice department and director of national intelligence, James Clapper, said it was necessary to continue seeking such legal extensions because the Congressional reform process supported by Obama was not yet complete.

"Given that legislation has not yet been enacted, and given the importance of maintaining the capabilities of the Section 215 telephony metadata program, the government has sought a 90-day reauthorization of the existing program," said the joint statement.

The 90-day blanket licence granted by the secretive Foreign Intelligence Surveillance Court, or Fisa court, is the fifth such extension that has been requested, and granted, since the Guardian first revealed the existence of the Section 215 program on 5 June 2013.

Similar 90-day reauthorisations were subsequently declassified by the administration on 19 July 2013, 11 October 2013, 3 January 2014 and 11 April 2014.Yet in March, Obama reacted to growing criticism of the NSA's domestic surveillance acitivities by calling for an end to bulk collection under Section 215 and suggesting that records be retained instead by telephone companies, and only be available for specific searches following court requests.

In May, the House of Representatives overwhelmingly passed the USA Freedom Act, which sought to enshrine this ban in law, although civil liberties campaigners claimed it was significantly watered down after pressure on legislators by government regulators.

In a statement explaining the latest renewal request on Friday, the justice department and office of the director of national intelligence said that they still support the legislation and would work with Congress to try to clarify the language before it is voted on by the Senate.

"Overall, the bill's significant reforms would provide the public greater confidence in our programs and the checks and balances in the system, while ensuring our intelligence and law enforcement professionals have the authorities they need to protect the Nation," the statement said.

"The administration strongly supports the USA Freedom Act. We urge the Senate to swiftly consider it, and remain ready to work with Congress to clarify that the bill prohibits bulk collection as noted above, as necessary."