Lady Gaga is adamant ... she did NOT ban Weird Al Yankovic from parodying her hit song "Born This Way" -- despite Al's accusation that the pop star shut him down hard recently.

Weird Al ripped into Gaga on his blog this morning -- claiming the egg-encased pop star strung him along for weeks while he tried to get her approval for his parody "Perform This Way" ... and ultimately rejected the proposal.

But sources extremely close to the singer tell us, "There must have been a misunderstanding because [Gaga] is in no way trying to block the release of the parody."

According to sources, "She's busy touring and hasn't heard the song yet. Her manager hasn't had a chance to play it for her yet" -- adding, "She's a huge Weird Al fan."