SHARES in construction group Birse hit an 18-month low yesterday as it warned it would incur yet more one-off charges from taking legal action over contracts.

The company, which has just begun work to build a £1.3m millennium footbridge across the River Tees at Stockton, revealed there would be a further write-off in the full-year results, to the end of April, 2001, from further litigation.

It would not say who the contract was with, nor how much the write-off would be, except to admit its value was £16m. The news sent Birse's shares tumbling 25 per cent to the lowest they have been since March 1999.