"He has contributed to revealing the extreme level of surveillance by nations against other nations and of citizens," former Socialist Left Party minister Baard Vegar Solhjell told AFP, explaining his move.

"Snowden contributed to people knowing about what has happened and spurring public debate" on trust in government, which he said was "a fundamental requirement for peace".

In a letter to the Norwegian Nobel Committee obtained by AFP, Solhjell and his party colleague Snorre Valen said that they do not necessarily condone or support all of Snowden’s disclosures, but praised him for revealing the "nature and technological prowess of modern surveillance".

"The level of sophistication and depth of surveillance that citizens all over the world are subject to have stunned us, and stirred debate," they wrote in the nomination letter.

They added that Snowden's actions have "led to the reintroduction of trust and transparency as a leading principle in global security policies".

US National Security Agency documents leaked by Snowden in 2013 revealed widespread surveillance of individuals and institutions in the United States and around the world.

According to the whistleblowing website Wikileaks, Snowden, who is currently living in Russia, applied for asylum in several countries, including Norway, last summer.

Solhjell, who was environment minister until Norway's left-wing government lost power last year, told AFP that he was aware of Snowden’s reported request for asylum and that it should be handled according to normal procedures.

"This matter has not affected our decision to nominate Snowden for the peace prize," Solhjell said.

The deadline for submitting nominations for the 2014 peace prize is February 1.

Among those elgible to forward nominations are politicians and barristers around the world, as well as university professors from certain disciplines.

In July 2013 a Swedish sociology professor, Stefan Svallfors, nominated Snowden for the Nobel Peace Prize after the deadline had passed but the nomination is still valid for 2014.