CNN– The US will begin training Ukrainian forces on how to operate Abrams tanks next month as it seeks to get them on to the battlefield against Russia before the end of the summer.

Thirty-one US M1A1 Abrams tanks – the size of a Ukrainian tank battalion – will be sent by mid-May to Grafenwoehr, Germany, where roughly 250 Ukrainians will undergo a 10-week training course with US troops, a US official told reporters traveling with Defense Secretary Lloyd Austin.

The tanks are a long-awaited capability for Ukraine, which has been battling Russia for more than a year.

Though the US had originally said it would send the newer M1A2 versions of the tanks, officials said in March that the Ukrainians would instead get the M1A1, dramatically accelerating the timeline for delivering the tanks.

Austin said Friday at the Ukraine Defense Contact Group in Ramstein, Germany, that in total the group of allies and partners has provided more than $55 billion in security assistance for Ukraine, including “more than 230 tanks and more than 1,550 armored vehicles and other equipment and munitions.”

“All of this is huge progress,” Austin said alongside Chairman of the Joint Chiefs of Staff Gen. Mark Milley. “And I am confident that this equipment and the training that accompanies it will put Ukraine’s forces in a position to continue to succeed on the battlefield.”

In addition to tanks being provided by the US, Ukraine will also be receiving German Leopard 2 tanks and British Challengers.

On Friday, Ukraine’s Defense Minister Oleksii Reznikov said that Poland will host a maintenance center for Leopard 2 tanks.

“Modern Western technology will result in Moscow’s defeat. The sooner it happens, the sooner peace will come,” Reznikov added.

Germany Defense Minister Boris Pistorius said the tank hub would cost around 150-200 million euros (around $164-219 million) per year and could be ready by the end of May.

The armored capability adds a powerful ground component to Ukrainian troops who have already endured more than a year of war. But the tanks may not have an immediate impact on the battlefield, given the time it takes to train on Western armor and the significant logistical demands to keep the complex systems running.

“Those saying, ‘Just give them the damned tanks!’ have likely never seen the choreography to making this work on the battlefield,” retired Army Lt. Gen. Mark Hertling, former commander of US Army Europe, previously told CNN. “In combat, get just a few things wrong and it causes disaster and failure. Lethal tanks turn into pillboxes that don’t move or shoot.”

Roughly 8,800 Ukrainian troops have already finished training in Germany and have returned to Ukraine, Col. Martin O’Donnell, spokesperson for US Army Europe and Africa, said in a statement Friday. Currently, there are approximately 2,250 Ukrainians conducting combined arms training in Germany.

“Putin thought that he could easily topple Kyiv’s democratically elected government. He thought that the wider world would let him get away with it. He thought that our unity would splinter,” Austin said of the Russian leader. “But he was wrong – on each and every count.”

In Germany on Friday, Milley said the tanks arriving for training in May “aren’t quite combat-capable” and will be used “to train the crews on how to shoot, maneuver, and maintain.”

And while Milley said he believes the tanks will be “very effective” on the battlefield against Russia, he emphasized that they will be most effective as one part of the equation.

“Wars are the outcomes of battles and wars are the function of many, many variables,” Milley said. “And in this case, you would have to make sure that your tanks are used in combined arms with mechanized infantry, artillery, all of that is synchronized with dismounted forces, etc. So there is no silver bullet in this case, but I do think the M1 tank when it’s delivered and it reaches its operational capability that it will be very effective on the battlefield.”

At the meeting on Friday, Reznikov, said his country was given a “green light” for “close cooperation” with NATO’s procurement agency.

“Ukraine has reached unprecedented levels of interoperability with NATO. We are, de facto, already a part of the alliance’s security space,” Reznikov said. “I expressed my hope that this would expedite political decisions regarding our country’s NATO integration.”

Milley said Friday that Ukraine’s military “continues to perform very well” in its fight against Russia.

“Russia continues to pay severely for its war of choice,” he said. “Unlike Ukrainian forces, who are highly motivated to fight for their country, to fight for their freedom, their democracy and their way of life, the Russians lack of leadership, they lack will, the morale is poor, and the discipline is eroding.”

This story has been updated with additional reporting