Construction equipment firm Ashtead Group says its full-year earnings are likely to be better than expected after a strong first quarter.

The company reported underlying profit-before-tax of £183.6m ($246.4m) in the three months to 31 July, a 4% improvement on the same period a year ago.

Rental revenue jumped 12% to £660.8m.

Ashtead chief executive Geoff Drabble said the first-quarter results were positively influenced by the fall in the sterling triggered by the UK's vote to leave the European Union.

"The underlying performance of the business continues to benefit from a clear and consistent strategy of organic growth supplemented by bolt-on acquisitions," he said in a statement.

"In the quarter, the reported results were positively impacted by weaker sterling but this was broadly balanced by lower gains on fleet disposals as we reduced our replacement capital expenditure.

"Both divisions are performing well, our end markets are strong and with the benefit of weaker sterling, we expect full-year results to be ahead of our expectations and the board continues to look to the medium term with confidence."