Energy services firm Wood Group posted results ahead of expectations as it grew revenue despite additional charges pushing it to a loss.

Shares in the firm swelled five per cent in early trading after the update.

It told investors its outlook remained unchanged as it hailed a recovery in its oil and gas division.

The firm also told investors its integration of its takeover of Amec Foster Wheeler was ahead of schedule, as it raised its three year cost-savings target from $170m to $250m.

Total revenue rose 13.4 per cent to reach $5.4bn (£4.2bn), while earnings took a 1.5 per cent hit down to $260m.

Profit swung from a slim $6m gain for the same time last year to a loss of $52m.

The FTSE 250 company's results were affected by non-cash amortisation charges of $125m, as well as exceptional costs of $101m.

Robin Watson, chief exec of Woods Group said the results reflected the "continued momentum in trading and delivery of cost and revenue synergies".

"Integration is ahead of schedule and we are increasing our three year cost synergy target from at least $170m to at least $210m.

"Our full year outlook is unchanged; we are seeing recovery in our core oil & gas market and good contract awards in broader industrial sectors," he added. "We remain on track to deliver growth in 2018 in line with previous guidance and market expectations."