In his open letter, Pompeo asked the conference to cancel the panel on which Snowden is supposed to speak and rescind his invitation, as allowing him to speak would "encourage lawlessness."
SXSW organizers refused to comply with his request.
"I appreciate his interest in SXSW, but I've never uninvited a speaker, and so we wouldn't do this with Snowden," said SXSW director Hugh Forrest. "Our goal here is to be an open platform. I'd love to have NSA giving a lecture."
"Snowden is going to urge this crowd of innovators to build better encryption into the next generation of [technology]. I'm proud and excited that Snowden wanted to get his message out at SXSW," Forrest added.
Snowden's lawyer Ben Wisner says he is trying to encourage Snowden to start talking and engaging more, joining the debate about surveillance and data privacy.