French construction and concessions firm Vinci said on Thursday it had been named preferred bidder for a 950 million-euro (796 million pounds) road maintenance contract with the London Borough of Hounslow.

The 25-year deal, which is subject to approval by the Department of Transport, will cover the upgrade and maintenance of 432 kilometres of road and 763 kilometres of pavement, Vinci said in a statement.

The contract is expected to start in January 2013.

(Reporting By Vicky Buffery)