The war of words between Iraq’s central government and authorities of the autonomous Kurdistan region over the control of oil resources took a sharp upturn this week, with Kurdish officials threatening secession over Baghdad’s failure to recognise its right to sign exploration contracts.

In a statement released late on Wednesday, Nechirvan Barzani, prime minister of the autonomous Kurdistan region, attacked remarks by oil minister Hussein al-Shahristani that appeared in the Iraqi press on Sunday. In the interview, Mr Shahristani said that the central government was not bound by contracts signed between international companies and the Kurdistan government.