State-owned energy firm Oil Industries Engineering & Construction (OIEC) has asked contractors to prequalify for a drilling deal covering offshore oil and gas wells on phase 20 of the giant South Pars gas field in Iran.

The firm, a subsidiary of National Iranian Oil Company (NIOC), says the work includes drilling a test well and 10 development wells on an engineering, procurement and drilling basis, according to state-run energy news agency Shana.

Phase 20 of South Pars will produce 2 billion cubic feet a day (cf/d) of gas, 75 million cf/d of ethane and 80,000 barrels a day of condensate.

In May, NIOC awarded a deal to OIEC to design and develop phases 20 and 21 of the South Pars field, with a total investment of $5.5bn. New refineries to process the gas will also be built near Kangan Port in the southwest province of Bushehr.

NIOC appears to have snubbed the UK/Dutch Shell Group after the oil major said in May 2008 it was considering developing the two phases of the gas field.