Iraq's parliament has delayed the start of debate on a newly revised oil revenue-sharing law following complaints from Sunni, Kurd and Shi'ite politicians.
The Iraqi Cabinet approved the measure unanimously on Tuesday, and the government had said parliament would begin debate on the law Wednesday.
However, of Iraq's 37 Cabinet ministers, at least 12 from Sunni and Shi'ite groups currently boycotting participation in the government were absent for the vote.
Loyalists of radical Shi'ite cleric Moqtada al-Sadr said they had rejected the draft.
Iraq's Kurdish regional government says it has not yet seen the measure. The government said if the Cabinet approved a text that is unacceptable to the Kurds, that would be a violation of their constitutional rights.
Representatives of the Iraq Accordance Front, a Sunni group, also expressed misgivings about the new oil law.
Even without their votes, Prime Minister Nouri al-Maliki should have enough support in Iraq's parliament to get the law passed, but not without jeopardizing Parliament's ability to help bring Iraq closer to national reconciliation.
The law is designed to fairly distribute the benefits of Iraq's oil reserves among Iraq's Kurds, Sunni Arabs and Shi'ite groups.
Iraq's oil reserves - the world's third largest - are mostly in the Kurdish north and Shi'ite dominated south. There is little oil in Iraq's central region where Sunnis are in the majority and they fear the new distribution formula will treat them unfairly.
Some information for this report was provided by AFP, AP and Reuters.