Donald Trump announced today that Vladimir Putin has agreed to supply the US with hundreds of thousands of tons of diesel, a move that could ease pump prices before Americans vote in November.

'I have just concluded a highly successful discussion with President Vladimir Putin, of Russia, wherein it was agreed that Russia will immediately supply over 300,000 tons of diesel fuel to the American and global marketplace,' Trump wrote on Truth Social.

The president said another 500,000 tons will be released in November and 1 million tons 'immediately thereafter.'

Trump added that 'based on the condition of their diesel refineries' - which have been decimated by Ukrainian drone strikes - 'Russia will then deliver, within a short period of time' another 3 million tons of diesel.

The Treasury Department simultaneously announced that it was easing sanctions on Russia through April 7 in order to facilitate the shipment of the diesel. Wide-ranging sanctions have been imposed since Russia's invasion of Ukraine.

Ukrainian President Volodymyr Zelensky trashed the deal as a 'gift to Putin', and Kyiv was caught off guard by the announcement, an official told Axios.

'Gifts to Putin will not bring peace or any benefit to the civilized world. Russia will "repay"' the diesel with further terror and treachery,' Zelensky said. 'Allowing Russia to sell petroleum products is an investment in a war that must be ended, not prolonged.'

The initial 300,000 tons works out at roughly 2.2 million barrels, less than two hours' worth of global diesel demand, according to calculations based on International Energy Agency figures. 

Even the 500,000 tons promised for November amounts to around 125,000 barrels a day, about an eighth of the roughly 1 million barrels of diesel Russia was exporting daily before Ukraine's refinery blitz.

Trump claimed that the agreement, in combination with America's 'total control of the Strait of Hormuz,' would bring down diesel prices for the world.

US diesel prices have soared to the highest on record amid the twin crises of the wars in Iran and Ukraine. The average price of a gallon stands at $6.28, more than $2.60 higher than the $3.68 recorded a year ago, according to AAA.

US diesel futures fell around 4.5 percent to $4.66 a gallon on Friday, while Brent crude, the global benchmark, traded at around $104 a barrel, down around 0.3 percent. 

Diesel powers the trucks and trains that move goods across America and most of the country's farm machinery, pushing prices higher for families. 

The cost of living has dominated voter concerns ahead of the November 3 midterms, with 47 percent of registered voters naming it the single most important factor in their vote in a Reuters/Ipsos poll conducted in late August. 

The deal with Putin comes after Trump reportedly pleaded with Zelensky to stop striking Russian oil refineries because the attacks were driving up diesel prices.

Trump repeatedly pressed Zelensky on the strikes during a September 20 call, and mentioned diesel multiple times, a source told Axios. 

The call came the same day Ukraine unleashed its largest drone attack on Moscow since the war began, with the city's mayor saying 450 drones were shot down and the capital's main oil refinery hit.

Ukraine has become increasingly adept at hitting the parts of refineries that take longest to fix, such as the units that turn heavy oil into diesel and jet fuel, which rely on equipment Russia cannot easily replace, analysts say.

Global oil prices were already pushed back above $100 a barrel last month after Iranian-backed militias in Iraq were blamed for a drone attack that shut Saudi Arabia's East-West pipeline.

Tehran's Houthi proxies in Yemen have also seized an island in the Bab el-Mandeb Strait at the mouth of the Red Sea, a vital route after Hormuz was disrupted.

Trump has blamed the diesel spike on Ukraine, rather than his own war with Iran, telling reporters at his golf resort in Ireland on September 13: 'This isn't done by the Middle East, this is done by what's happening with Russia and Ukraine.'