UPDATE 1-Singapore's GIC joins Fortress bid for UK supermarket Morrisons

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LONDON, July 28 (Reuters) - Singapore's sovereign wealth fund has joined the Fortress-led private equity consortium making a recommended offer for the British supermarket group Morrisons, the companies said on Wednesday.

Britain's fourth largest supermarket has agreed to a takeover led by SoftBank-owned Fortress Investment Group, valuing it at 6.3 billion pounds ($8.8 billion). Two other private equity groups, CD&R and Apollo, have also shown interest.

However the Fortress-led group may still have more work to do after Morrisons' biggest shareholder, Silchester, said on Tuesday it was not inclined to support the deal because there was little in the offer that could not be achieved as a listed company.

Silchester owns a 15.14% stake in Morrisons. The offer agreement includes a scheme of arrangement with a 75% hurdle for shareholder acceptance and squeeze out.

GIC, Singapore's sovereign wealth fund, holds around 0.21% of the issued share capital of Morrisons.

($1 = 0.7202 pounds) (Reporting by Kate Holton, Editing by Paul Sandle and Sarah Young)