The United Arab Emirates (UAE) said on Tuesday it quit OPEC and OPEC+, dealing a heavy blow to the oil exporting groups and ​their de facto leader, Saudi Arabia, at a time when the Iran ‌war has caused a historic energy shock and unsettled the global economy.

The statement was delivered as Opec prepared to meet in Vienna on Wednesday. It will also leave the broader Opec+.

“This decision follows a comprehensive review of the UAE’s production policy and its current and future capacity and is based on our national interest and our commitment to contributing effectively to meeting the market’s pressing needs,” UAE state news agency Wam said.

“While near-term volatility, including disruptions in the Arabian Gulf and the Strait of Hormuz, continues to affect supply dynamics, underlying trends point to sustained growth in global energy demand over the medium to long term.”

The decision will take effect on May 1.

Wam said the decision “reflects a policy-driven evolution in the UAE’s approach, enhancing flexibility to respond to market dynamics while continuing to contribute to stability in a measured and responsible manner”.

The stunning loss of the UAE, a longstanding OPEC member, could create disarray and weaken the group, ​which has usually sought to show a united front despite internal ​disagreements over a range of issues from geopolitics to production quotas.

OPEC ⁠Gulf producers have already been struggling to ship exports through the Strait of ​Hormuz, a narrow chokepoint between Iran and Oman through which a fifth of ​the world’s crude oil and liquefied natural gas normally passes, because of Iranian threats and attacks against vessels.

But the UAE exit from OPEC represents a big win for US ​President Donald Trump, who has accused the organisation of “ripping off the rest ​of the world” by inflating oil prices.

Trump has also linked US military support for the ‌Gulf ⁠with oil prices, saying that while the US defends OPEC members, they “exploit this by imposing high oil prices”.

The move came after the UAE, a regional business hub and one of Washington’s most important allies, criticised fellow Arab ​states for not doing ​enough to protect ⁠it from numerous Iranian attacks during the war.

Anwar Gargash, the diplomatic adviser for the UAE president, criticised the Arab ​and Gulf response to the Iranian attacks in a ​session at ⁠the Gulf Influencers Forum on Monday.

“The Gulf Cooperation Council countries supported each other logistically, but politically and militarily, I think their position has been the weakest ⁠historically,” ​Gargash said.

“I expect this weak stance from the ​Arab League and I am not surprised by it, but I haven’t expected it from the (Gulf) ​Cooperation Council and I am surprised by it,” he said.