Oil and gas services firm Petrofac said it expected net profit in 2015 to be around $500 million, citing lower oil price environment, change in project timings and a settlement related to its project in Shetland, Scotland.

Petrofac's guidance falls short of market consensus, which was a net profit of $688.1 million, according to Thomson Reuters I/B/E/S.

The British company, which builds and maintains oil and gas facilities, said current 2015 forward curve for oil price could reduce net profit at its integrated energy services unit by around $45 million.

Oil prices have been falling since the summer due to abundant supply - partly from U.S. shale oil - and low demand growth, particularly in Europe and Asia.

Brent crude futures had fallen 34 per cent since June to touch a four-year low of $76.76 a barrel on Nov. 14.

Petrofac also said net profit for this year would come in towards the lower end of its previous guidance range of $580 million to $600 million.-Reuters