GCHQ's internet mass surveillance programmes are lawful and do not violate human rights, a tribunal has ruled.

The Investigatory Powers Tribunal (IPT) made the ruling in a case that rights groups brought against the UK government over alleged mass surveillance on citizens via programmes run by the British intelligence agency GCHQ and the US National Security Agency. Both programmes were brought to light in documents leaked by Edward Snowden last year.

However, those programs are legal under the 14-year-old Regulation of Investigatory Powers Act (RIPA), which regulates the government's surveillance powers, the Tribunal ruled last week.

"The 'Snowden revelations' in particular have led to the impression voiced in some quarters that the law in some way permits the Intelligence Services carte blanche to do what they will. We are satisfied this is not the case," the IPT said in its ruling, which was published by complainant Privacy International.

However, the tribunal, which was set up in 2000 to deal with complaints relating to the use of covert techniques, did ask for more comments about whether receiving bulk intercepted material from foreign intelligence agencies such as the NSA would be legal.

Not satisfied with the outcome, Privacy International and its co-claimant, Bytes for All, will lodge an appeal to the European Court of Human Rights, challenging the Tribunal's finding that mass surveillance could comply with human rights.

In addition, the groups will also ask the European Court of Human Rights to scrutinise GCHQ's actions against Britain's human rights obligations to respect citizens' rights to privacy and freedom of expression, enshrined in Articles 8 and 10 of the European Convention on Human Rights, they said.