UPDATE 1-Anglo American to sell holding in Tongaat Hulett

* Plans to sell holding to institutional investors

* Proposes accelerated bookbuild, exchangeable bond issue

(Adds details)

LONDON, Aug 12 (Reuters) - Miner Anglo American Plc (AAL.L) said it plans to sell its holding in diversified agri-processing group Tongaat Hulett Ltd (TONJ.J) to institutional investors via an accelerated bookbuild and an exchangeable bond issue.

Anglo said on Wednesday it will offer its entire holding of 51.2 million Tongaat shares, about 49.5 percent of Tongaat's listed shares. It did not announce pricing details.

Tongaat shares traded at 94.99 rand at 0721 GMT, valuing Anglo's holding at about 4.85 billion rand ($594 million).

Anglo, which is fending off a merger proposal from Xstrata Plc (XTA.L), said 2 billion rand of the exchangeable issue is underwritten by FirstRand Bank Ltd.

On Aug 3, Tongaat posted a jump in first-half headline earnings, boosted by higher world sugar prices and the consolidation of its Zimbabwe business, but said it expects a tougher second half. [ID:nL3581925]

(Reporting by Julie Crust; editing by Paul Sandle)

($1=8.171 South African Rand)