A record release of strategic oil reserves has been agreed in a bid to help offset supply disruption since the Middle East conflict began.
The International Energy Agency (IEA) said it would coordinate a flow of 400 million barrels into the market, with the UK government contributing 13.5 million barrels.
The body has barrels at its disposal following talks with ministers from the G7 group of advanced industrialised nations, including the UK.
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The move, however, made little difference to oil prices.
Brent crude, the international benchmark, has eased back from highs this week above $118 per barrel on news that the aid was being considered.
It was trading at $92 a barrel shortly before the details were confirmed on Wednesday afternoon and dipped only to $90.63 after the announcement.
It's not clear when the emergency stocks will come on stream, with the IEA saying they will be made available to the market "over a timeframe that is appropriate to the national circumstances of each member country".
Implementation details for the policy will be announced in due course, the IEA said.
Why's it been announced?
The Gulf region usually exports about 15 million barrels of oil and five million barrels of oil products per day but output and deliveries have been shattered by Iranian attacks on energy infrastructure since US-Israeli military strikes against the regime in Tehran began last month.
The threat to shipping has effectively closed the narrow Strait of Hormuz, off the Iranian coast, which usually handles a fifth of the world's energy shipments and export volumes of crude and refined products are currently less than 10% of pre-conflict levels.
How much do members hold?
The 32 IEA members, of which the UK is one, hold emergency stockpiles of over 1.2 billion barrels, with a further 600 million barrels of industry stocks held.
The announcement is the sixth coordinated stock release since the IEA was founded in 1974.
Previous actions were taken during the Gulf War in 1991, due to Hurricane Katrina in 2005, intervention in Libya in 2011, and twice in 2022 after the invasion of Ukraine.
(c) Sky News 2026: Biggest ever release of oil reserves to ease war supply disruption
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