SHARES in oil and gas services company Petrofac have risen seven per cent after it maintained its annual profit guidance.

The group, which employs around 4,500 people in Scotland, said it had seen strong performance from its engineering and construction arms in the second half of its financial year.

Petrofac had seen net profits tumble 44 per cent to $136 million (£82m) in the first six months of the year, partly as a result of delays in getting the Greater Stella field in the North Sea into production. It had forecast at the time that performance was likely to improve as the year wore on.

With oil prices continuing to fall, investors appeared pleased that Petrofac remained confident on its full-year forecast of net profits between $580m and $600m. Shares closed up 72.5p at 1060p.

Petrofac said its pipeline of bidding opportunities at its engineering and construction business, which accounts for nearly 60 per cent of total revenue, remained strong, with customers investing heavily across its core geographies.

Across all operations the order rose to $21.2 billion, from $20.3bn.

Ayman Asfari, Petrofac chief executive, said new order intake was being maintained at margins in line with recent years. In operations around Scotland, Petrofac highlighted further progress at the Laggan-Tormore gas plant on Shetland and "substantial mechanical completion" is expected by the year end.

For Greater Stella, which is operated by Ithaca Energy, Petrofac is modifying a floating production storage and offloading vessel. It said: "We continue to advance construction activities on the main deck of the vessel, with all the main oil and gas processing plant packages in place and installation of the associated pipework and cabling in progress.

"First production on the Greater Stella Area development in the UK North Sea is planned for mid-2015."

It also pointed to an engineering and support contract worth up to £120m for Chevron's Captain, Alba and Erskine platforms in the central North Sea.

Operations in Iraq, which account for less than five per cent of revenue, were said to be unaffected by conditions in the wider region so far.