Pakistan, June 8 -- OPEC+ agreed on Sunday a fourth increase in its oil output targets in as many months, OPEC said in a statement, even though the U.S. war with Iran is still preventing several of the group's members from pumping more.

The war has cut oil flows via the Strait of Hormuz, creating the world's biggest-ever supply crisis as key OPEC+ members including Saudi Arabia have been unable to supply customers in full since the end of February. The crisis for OPEC+ deepened when the United Arab Emirates left the Organization of the Petroleum Exporting Countries after almost 60 years.

Seven core members of OPEC+, which groups OPEC and allied producers including Russia, have increased their output quotas from April to June by almost 6...