American TV comedian Stephen Colbert was joking about invading Saskatchewan this week — prompting a quick response from Premier Brad Wall.

"Back off, Colbert," Wall tweeted on Tuesday.

On Monday night, Colbert was interviewing Michael McFaulformer U.S. ambassador to Russia, who observed that Vladimir Putin's popularity has gone up in response to recent moves in Ukraine.

Faul noted that Putin's approval rating in his own country is now around 80 per cent, while Obama's is around 40.

"Maybe Obama should invade ... Saskatchewan, something like that," Colbert said.

"I don't think that would be wise," McFaul replied.

TV-Colbert-Get Lucky Colbert Report 2010

TV funnyman Stephen Colbert has raised the spectre of the U.S. invading Saskatchewan to boost Barack Obama's approval rating. (Scott Gries/Comedy Central/AP)