Paul Whelan ain't happy that he's still behind bars in Russia ... saying Thursday he's "disappointed" with Joe Biden and his administration after he wasn't included in the Brittney Griner deal.
Whelan spoke with CNN from a penal colony in Russia just hours after the U.S. successfully swapped arms dealer Viktor Bout for Griner ... and he expressed angst that he's still behind bars -- while the WNBA star is on her way home.
"I am greatly disappointed that more has not been done to secure my release, especially as the four year anniversary of my arrest is coming up," said Whelan, who's been locked up in Russia on espionage charges since 2018.