Whistleblower Edward Snowden has expressed his willingness to testify before a German parliamentary committee investigating surveillance activities of the US National Security Agency (NSA), media reported on Friday.

The former NSA contractor said he was ready for a detailed testimony in Germany without any conditions, German media reported, citing a letter from Snowden's attorney in Berlin to the inquiry committee of the Bundestag, lower house of German parliament.

Snowden's words came amid a dispute in Berlin about whether the German NSA panel should seek testimony from him in its investigative process.

Glenn Greenwald, who had published leaks that exposed the NSA monitoring program "Prism" on the basis of classified documents from Snowden, showed support for calling him as a witness, German media said.

In a recent interview, the NSA-leak reporter said the US spying scandal cannot be fully clarified without a testimony from Snowden, adding that there would be huge loopholes in their inquiry if German investigators don't question Snowden personally.

The German parliamentary committee, formed less than a month ago, is charged with the task of investigating spying on German communications by the NSA and other intelligence services.

The inquiry, comprising of six lawmakers from the ruling coalition and two from the opposition, has led a troubled early existence. Its chairman Clemens Binninger resigned his post suddenly on Wednesday, just a few days after the panel's first meeting.

Binninger told media that he quit because of the different opinions among the committee about a possible Snowden testimony. The opposition has been urging to summon Snowden, while members of ruling parties doubted if he could provide crucial information for clarifying the espionage scandal.

On Thursday, the inquiry voted by majority to discuss the Snowden issue at its next meeting on May 8 - just after German Chancellor Angela Merkel's visit to the United States.

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