MOSCOW: Three tankers carrying Russian diesel are en route to the United States, with a fourth expected to depart Wednesday, Moscow said, part of a deal that triggered a fierce Ukrainian and European backlash.

US President Donald Trump this month struck an agreement with Russia's President Vladimir Putin to ease sanctions in exchange for Moscow releasing diesel onto global markets.

The measure was seen as an attempt to lower fuel prices for American consumers ahead of the US midterm legislative elections on November 3, and drew sharp criticism from Ukraine and its allies.

"At present, three tankers" with Russian fuel are on their way to the United States, Russian Deputy Prime Minister Alexander Novak told reporters on Tuesday. A fourth was expected to set off on Wednesday, he added.