UPDATE 1-Moody's cuts ratings on S.Africa's Eskom, Telkom

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JOHANNESBURG, Oct 1 (Reuters) - Credit agency Moody's on Monday cut its rating on South African power utility Eskom , fixed-line operator Telkom SA and 12 municipalities, following a similar downgrade of Africa's top economy last week.

It also lowered its outlook on miner Gold Fields Ltd

to "stable" from "positive", citing concern about the impact of labour unrest on South Africa's mining industry.

The agency said in a statement it cut Eskom's senior unsecured bond rating by one notch, to Baa3 from Baa2, a move that could drive up borrowing costs for the utility as it looks to fund infrastructure spending.

The state-owned utility is expected to tap the bond market for some of a planned 300 billion rand ($36.06 billion) in funding.

Moody's made a similar cut to Telkom's rating, which was also lowered to Baa3, while 12 local governments had their long-term ratings cut.

The agency on Thursday cut the government bond rating of Africa's top economy by one notch, citing worries about the negative investment climate - from creaking infrastructure to concerns about future political stability.

Investor sentiment has been soured by a series of wildcat strikes in the mining industry in recent weeks, which have hamstrung production in the world's top platinum producer and No.4 gold producer.

Critics have also charged that the strikes have exposed President Jacob Zuma's ruling African National Congress as ineffectual and out of touch with millions of poor South Africans. ($1 = 8.3194 South African rand)

(Reporting by David Dolan; editing by Andrew Hay)

((david.dolan@thomsonreuters.com)(+27 11 775 3150)(Reuters Messaging: david.dolan@thomsonreuters.com@reuters.net))