Rep. Ron Paul (R-TX) claimed that the Obama administration's move to impose a no-fly zone over Libya was "unconstitutional" because the president didn't seek Congressional authorization.

In a video posted Friday to YouTube, the isolationist congressman called the no-fly zone -- pushed by the U.S., Britain and France and approved by the United Nations -- "an act of war" that's illegitimate without Congress's approval.

"The no-fly zone is unconstitutional because Congress has not authorized it," Paul said in the video, adding: "Where did the president get the authority to impose a no-fly zone over Libya?"

President Barack Obama insisted that the U.S. will not officially go to war with Libya, and that there will be no ground troops for the air-only mission aimed at preventing a humanitarian disaster waged by leader Muammar Gaddafi.

Watch the video, via Ron Paul's YouTube account.