A US congressman has stated that he is "deeply troubled" by the appearance of "common criminal" Edward Snowden at the South by Southwest (SXSW) Interactive Festival and has urged the organisers to withdraw the whistleblower's invitation.

Snowden, a former contract worker for the National Security Agency (NSA), is due to appear at the festival which takes palce in Texas via video-link on Monday at 11am local time (4pm GMT) to talk about the impact of the agency's spying practices.

In an open letter to the festival's organisers Congressman Mike Pompeo, a member of the House Intelligence Committee, referred to Snowden as both a "traitor" and a "common criminal".

He wrote: "I am deeply troubled to learn that you have invited Edward Snowden to address SXSW on privacy, surveillance, and online monitoring in the United States."

"Mr. Snowden's appearance would stamp the imprimatur of your fine organization on a man who ill deserves such accolades. Rewarding Mr Snowden's behavior in this way encourages the very lawlessness he exhibited. I strongly urge you to withdraw this invitation."

Snowden is currently living in Russia having previously claimed that there was "no chance" of him receiving a fair trial in the US due to failings in the current law.

The fact that he has sought asylum in Russia is a major criticism of Pompeo.

"While reasonable people can and should disagree on major policy issues in a free society, Mr Snowden has, through his own actions, demonstrated he has no interest in contributing to a free society, choosing instead to live in Russia—a country in which political dissidents are jailed and individual rights have not been respected since at least 1917," Pompeo stated.

The interview will be conducted by Christopher Soghoian from the American Civil Liberties Union and will be moderated by Snowden's US-based legal adviser Ben Wizner. It will be the first time that Snowden has taken part in a live video interview in public.

Live streaming of the event can be found at the Texas Tribune website. The video recording will also be made available by ACLU after the event here.