TRIPOLI (AFP) - Libya's interim assembly said it was facing an impending "coup" on Tuesday after ex-rebel militias gave it a five-hour deadline to stand down.

"The General National Congress strongly denounces this attack against the authorities and categorically rejects the content of this statement, which it deems a coup d'etat," the assembly's speaker Nuri Abu Sahmein told MPs.

Earlier this month, the assembly stirred widespread criticism by extending its interim mandate, three years after the overthrow of the 42-year dictatorship of Moamer Kadhafi.