RABAT, Nov 29 (Reuters) - Morocco's Cherifien des Phosphates (OCP), one of the world's biggest phosphate producers, plans to issue 5 billion dirhams ($495 million) of domestic perpetual bonds, the stock exchange regulator said on Tuesday.

State run OCP, a major earner of foreign currency for Morocco, has been increasing output to help offset a slide in prices and aims to produce 47 million tonnes of crude phosphate rock annually in coming years, up from about 30.3 million in 2015, according to the bond prospectus, published on the stock market regulator's (AMMC) website.

It also plans to ramp up fertiliser production to 12 million tonnes in 2017 from 5.3 million in 2015.

The details and timing of the subordinated bond issue have yet to be decided, the regulator said.

It is OCP's first domestic bond issue since 2011, as the group wants to diversify its funding sources. Last year it raised $1 billion in an international bond issue.

The prospectus said AMMC had approved the bond issue on Monday. The bonds will be issued in one or several tranches and some would be listed on the Casablanca stock exchange.

OCP, which reported a 23 percent drop in first-half profit in September due to low prices, plans to invest around $20 billion over 2008-25 and signed a deal with Ethiopia this month to build a $3.7 billion plant to produce fertilisers.

($1 = 10.0890 Moroccan dirham)

(Reporting By Aziz El Yaakoubi; Editing by Susan Fenton) ((aziz.elyaakoubi@thomsonreuters.com; +212623934595))