Iraq, which had one of the worst compliance rates in May according to a Reuters survey of OPEC production, agreed to the additional pledge, OPEC sources said.
"The Saudis have been pushing Baghdad hard to comply," one OPEC+ source said. "Iraq has agreed to the pledge to improve its full compliance with the cuts."
Baghdad blamed technical reasons and a recent change in its government for weak compliance in May, another OPEC source said.
The OPEC+ technical and ministerial committee meetings, which review the market and usually make recommendations on policy, were now scheduled for June 17 and 18, OPEC+ sources said.