SYDNEY, July 28 (Reuters) - Rio Tinto said on Thursday that its Guinea subsidiary Simfer has formed a joint venture with the government and the Chinese-backed consortium Winning Consortium Simandou (WCS) to co-develop the Simandou iron ore mine project.

The joint venture incorporation, called La Compagnie du TransGuinéen (The TransGuinean Company), will be central for the co-development of the rail and the port components of the Simandou iron ore development project, Rio said in a statement.

The miner said the parties would will now work on a "shareholding agreement, finalising cost estimates and funding, and securing all necessary approvals and other permits and agreements required to progress the co-development of infrastructures."

The announcements comes after the Guinea government ordered a halt to work at the project earlier this month, after Simfer and WCS missed an extended deadline to agree on a joint venture.

Rio Tinto has held rights to Simandou since 1997. Through Rio Tinto Simfer, it owns a 45.05% stake in the southern half, Blocks 3 and 4, of the deposit, with Aluminium Corp of China (Chinalco) holding 39.95% and Guinea's government the remaining 15%.

WCS holds Blocks 1 and 2 of Simandou. (Reporting by Praveen Menon; Editing by Sam Holmes)