Edward Snowden, the man behind the exposés on mass automated surveillance by the U.S. National Security Agency, has vowed that he would not reveal official secrets that could harm the U.S., “even under torture”.

In an unusual exchange of e-mails with a former Republican Party Senator, Gordon Humphrey of New Hampshire, Mr. Snowden said his knowledge of encryption and other forms of data protection meant that “no intelligence service, not even our own” had the capacity to compromise the secrets that he continued to protect.

He explained to the Mr. Humphrey that during his time at the Pentagon’s Defence Intelligence Agency he taught people “how to keep such information from being compromised even in the highest threat counter-intelligence environments, i.e. China”.

Mr. Humphrey confirmed to Glen Greenwald, the journalist who broke the stories on Mr. Snowden’s exposés, that he initiated the e-mail exchange with a message that said Mr. Snowden had “done the right thing in exposing what I regard as massive violation of the U.S. Constitution”.

Further, Mr. Humphrey added, he regarded Mr. Snowden a “courageous whistleblower” and objected to the “monumentally disproportionate campaign being waged by the U.S. Government against [Mr.] Snowden, while no effort is being made to identify, remove from office and bring to justice those officials who have abused power, seriously and repeatedly violating the Constitution... and the rights of millions of unsuspecting citizens.”

He also urged that Americans, including former members of the U.S. Congress, who were concerned about the “growing arrogance” and “increasingly menacing nature” of their government, ought to help Mr. Snowden find political asylum in another country.

Meanwhile, Microsoft said in a blog post that it had written to U.S. Attorney General Eric Holder, requesting him to “personally take action” to permit Microsoft to share more information about the way they handle national security requests for customer data.

Earlier, Guardian reports said Microsoft had “collaborated closely” with U.S. intelligence services, even helping the NSA “circumvent the company’s own encryption” “circumvent the company's own encryption,” to intercept web chats on the new Outlook.com portal and gave the Agency “pre-encryption stage access to email on Outlook and including Hotmail.

In addition the company was said to have given the NSA access to its cloud storage service SkyDrive and helped the Agency “triple” the amount of Skype video calls being collected through its PRISM surveillance programme.

More In: International | News | World