WASHINGTON - The Pentagon plans to speed up the delivery of Abrams tanks to Ukraine, a US official and a source familiar with the situation said, providing the vital equipment to Kyiv as soon as this autumn.

In January, the Biden administration pledged to supply Ukraine with 31 advanced M1A2 Abrams tanks after months of shunning the idea of deploying the difficult-to-maintain tanks to Ukraine.

The new plan would give Ukraine the M1A1 SA Abrams tank variant, which can run on diesel fuel like the majority of the Ukrainian fleet, one of the officials said.

The change also speeds up delivery by about a year, according to a congressional aide briefed on the matter.

A Pentagon spokesman declined to comment on the faster timeline because the Department of Defence had not previously offered any specific date for its effort to get the tanks into Ukrainian hands, only saying it would take “months.”

“We’re working on that,” White House spokesman John Kirby told MSNBC on Tuesday.

“There’re some changes that you can make to the process to sort of speed that up.”

US Defence Secretary Lloyd Austin has looked at several options for quickening the delivery and arrived at a determination that would reduce the time by about a year, a congressional aide briefed on the plan told Reuters.

Examples for options Mr Austin could have evaluated included changing positions in the delivery queue, or using US tanks that have had their sensitive equipment removed, so that it cannot be captured and studied by Russian troops.

The General Dynamics Corp production line is currently completing about 12 Abrams tanks a month.

Funds to alter or buy Abrams tanks would come from a fund known as the Ukraine Security Assistance Initiative (USAI), which allows President Joe Biden’s administration to get weapons from industry rather than draw from US weapons stocks.

There is a round of USAI funding being prepared for later this month, said sources who spoke on condition of anonymity. REUTERS