Talks in Doha, Qatar among the world's biggest oil producers broke up after failing to have failed to reach a deal on freezing output and and boosting sagging oil prices.

Qatari Energy Minister Mohammed Saleh al-Sada said after six hours of negotiations that consultations would continue between the parties until an OPEC meeting in June.  Until then, "All participating countries will consult among themselves and with others," he said.

Sunday's talks in Qatar's capital were unusual in that they brought together members of the Organization of the Petroleum Exporting Countries and non-OPEC nations such as Russia.  But the discussions were beset with regional rivalries, and Iran refused to take part.  Tehran is ramping up production after international trade sanctions were lifted as part of the nuclear deal it signed with world powers.  Iran does not want to agree to any production cut until after it has reestablished the market share it had before the sanctions went into force.

"As we're not going to sign anything, and as we're not part of the decision to freeze output, we ultimately decided it was not necessary to send a representative," read a statement from the Iranian government. 

The economies of Russia and OPEC members Ecuador and Venezuela are being hit hardest by the low prices, with governments being forced to contemplate a "post-oil" era of economic diversification.