G7 leaders have agreed to release up to 100 million barrels of oil and refined fuels from emergency reserves over the next four months. Here is what the move means.

The decision was taken on October 2 at an emergency meeting chaired by French President Emmanuel Macron. The release will be supervised by the International Energy Agency, with a large amount of diesel released in the first 20 days.

The trigger was record fuel prices. Diesel in the United States hit a record USD 6.53 a gallon. In Europe, diesel averaged 2.24 euros a litre, also an all-time high.

Pressure had been building from Washington. President Trump threatened a ban on American diesel exports unless Europe released stocks. The G7 pledged no export bans between members.

This follows a 400-million-barrel release announced in March. With US midterm elections on November 3, fuel prices are a live political issue on both sides of the Atlantic.