Petrofac's order backlog rises to $20.5 bln

(Adds share movement, analyst comment, background)

June 23 (Reuters) - Oilfield services provider Petrofac Ltd said strong performance at its engineering and construction division had helped increase its order backlog to $20.5 billion at the end of May.

Petrofac shares rose as much as 11 percent to 965.5 pence on the London Stock Exchange (Other OTC: LDNXF - news) on Tuesday morning.

The company, however, said it expected pretax costs at its Laggan-Tormore project to increase by about 30 million pounds ($47.35 million) as it began additional completion and pre-commissioning works.

The company has incurred about 140 million pounds in costs on the project so far this year.

Petrofac has been taking heavy losses on the Shetland Islands project, buckling under the North Sea's hostile environment and the high cost of doing business in the region.

The company had said in April it expected a pretax loss of about 130 million pounds in 2015, in addition to the $230 million it recognised in February.

Laggan-Tormore, a high-quality oil and gas asset 80 percent owned by French oil major Total (Swiss: FP.SW - news) , is expected to yield about 93,000 barrels of oil equivalent per day at its peak.

Order backlog at Petrofac's Engineering, Construction, Operations and Maintenance (ECOM) division, which accounted for nearly 80 percent of its revenue last year, grew 12 percent from the end of December.

JP Morgan Cazenove analyst Daniel Butcher said Petrofac's ECOM backlog, which was $17.4 billion at the end of May, had the potential to increase to $20 billion for the first half.

Chief Executive Ayman Asfari said the company stood to secure several contracts in the second half of the year as clients were investing in large projects in its core markets.

The company said it expected its net profit for the year to be weighted towards the second half as several projects were near completion.

($1 = 0.6338 pounds) (Reporting by Abhiram Nandakumar in Bengaluru; Editing by Anupama Dwivedi)