BAE Systems said it would take a £160 million charge in its first half due to a cost over-run on its Omani offshore patrol vessel contract.

The work is being done by the surface ships business, based partly on the Clyde, but the contract relates entirely to BAE’s Portsmouth base.

The programme for three offshore patrol vessels for Oman is one of two loss-making export ship contracts the group acquired from VT Group as part of last year’s consolidation of the naval surface shipbuilding industry. BAE has already taken a £100m charge from the termination of a VT contract from Trinidad and Tobago.

BAE shares were down 3p at 309.9p. The stock has shed around 6% since the start of the year.