MADRID, Sept 8 (Reuters) - Spain's CNMV market supervisor on Wednesday approved the partial takeover bid for energy group Naturgy by Australian fund IFM, which sets the clock ticking to launch the 4.9 billion euros ($5.79 billion) transaction.

IFM has up to five days to make a public announcement. Once the bid and its conditions have been announced publicly, Naturgy shareholders have 30 days to accept the offer.

(Reporting by Jesús Aguado; Editing by Nathan Allen)