The former Buffy the Vampire Slayer actress was asked a number of questions about the series on Bravo's Watch What Happens Live.
Host Andy Cohen asked Hannigan which cast member was the "most annoyed" to be on the show by the end of its run.
She replied: "Sarah. She had a big career going. It was a lot of work."
Initial quotes from the interview by Zap2it claimed that Hannigan was asked who the "most annoying" cast member was, but this was later corrected.
Hannigan later took to Twitter to reassure fans that she did not mean to "diss" her former co-star.
@evanrosskatz it wasn't a diss! She said that herself!She did an interview saying that is why the show was ending!No diss, just fact.— alyson hannigan (@alydenisof) May 9, 2013
Hannigan was also asked if there were any secret "on-set hook-ups" between the cast.
She replied: "I think Nick [Brendan, who played Xander] and I might have kissed once... he might have had a boob or something."
The How I Met Your Mother actress was recently granted a restraining order against a man accused of making threats.
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