The move was the latest in a long-running dispute over energy contracts and revenues between Baghdad and the autonomous region, with the two sides squabbling over payments, revenue-sharing and Baghdad's refusal to recognise dozens of contracts Kurdish officials have signed with foreign energy firms.

"The MNR (Ministry of Natural Resources) has reluctantly decided to reduce exports to 50,000 bpd (barrels per day) with a view to possible cessation in one month unless payments are forthcoming" for companies working on oilfields, the Kurdish government said in a statement in English on its website.

It added that the Kurdistan region was "committed to the export target of 175,000" bpd agreed in Iraq's 2012 federal budget, and said it could even export more "if the federal government honours its commitments to pay."

Kurdistan said in May 2011 that Iraq had paid oil contractors in the autonomous region as part of an "interim agreement on revenue allocation."

The region has signed around 40 contracts with international companies on a production-sharing basis without seeking the express approval of the central government's oil ministry.

The federal oil ministry, meanwhile, has awarded energy contracts to international companies on the basis of a per-barrel service fee. It has also refused to sign deals with any firm that has agreed a contract with Kurdistan.

Baghdad has also yet to approve an oil and gas law that would regulate the sector, with proposals languishing for several years.