This paper presents an automatic grapheme to phoneme conversion system that uses statistical machine transla- tion techniques provided by the Moses Toolkit. The gen- erated word pronunciations are employed in the dictio- nary of an automatic speech recognition system and eval- uated using the ESTER 2 French broadcast news cor- pus. Grapheme to phoneme conversion based on Moses is compared to two other methods: G2P, and a dictionary look-up method supplemented by a rule-based tool for phonetic transcriptions of words unavailable in the dictionary. Moses gives better results than G2P, and have performance comparable to the dictionary look-up strat- egy.