Iraq’s Oil Ministry has postponed the bid deadline for the construction of its integrated Nasiriya oil field and refinery indefinitely after several previous delays.

Prequalified contractors were expected to bid on 19 June for the project, but the submission of proposals has now been delayed for the third time since December.

“The reason for the postponement is to complete technical and administrative preparations for the auction,” the Oil Ministry said in a statement, with no new deadline set.

According to reports, there are five companies prequalified to bid on the project in the south of Iraq: Indian groups Essar and ONGC; South Korea’s GS Engineering & Construction; France-based Maurel et Prom; and Russia’s Rosneft.

The indefinite delay came as Iraq was plunged into a security crisis with militants from the Islamic State in Iraq and the Levant (Isis) taking control of the city of Mosul and large areas of the north of the country.

While southern oil assets are not currently under direct physical threat at present, analysts believe the latest developments could affect the expansion of oil production in Iraq in the medium term.

The original deadline for bids was in December, but this was pushed by to 23 January and subsequently delayed further to 19 June.

The project covers the development of the Nasiriyah oil field in the Thi-Qar province in southern Iraq, along with the construction and operation of a new integrated 300,000 barrel-a-day (b/d) refinery, the largest in a raft of new downstream facilities planned by Iraq.

The front-end engineering and design (feed) on the refinery, located 200 kilometres north of Basra and 400km south of Baghdad, was completed by Foster Wheeler.

The scope of the refinery facilities contains 27 process units of two identical trains and a common fluid catalytic cracker (FCC) catalyst complex.