All 31 American M1A1 Abrams tanks promised to Kyiv by the administration of U.S. President Joseph Biden have arrived in Ukraine, U.S. Army Europe and Africa Spokesman Martin O'Donnell told the Voice of America.

He said all Ukrainians who were trained on tanks as part of American forces in Germany also returned to their homeland along with ammunition and spare parts for tanks.

"We have lived up to our end of the bargain. From this point forward, it is up to them [Ukraine] to determine when and where they will deliver this capability," O'Donnell said.

Before sending the Abrams to the battlefield, it could take some time for Ukrainian troops to ensure they have the necessary support elements and determine when and where to use the tanks to best effect against Russian forces, military officials said.

"I think Ukraine will be deliberate in when and where they use it. The Abrams tank is one hell of an armored vehicle, but it's not a silver bullet. Ultimately, it's Ukraine's determination to break through that matters most," O'Donnell said.

It is noted that the Abrams will be added to other Western tanks already in service with Ukraine, which is fighting to return territories seized by Russia in the eastern and southern regions of the country.

The Abrams tanks’ arrival in Ukraine comes as the United States provided up to $200 million in additional military aid for Ukraine in a package last week. The Pentagon said the package included weapons for air defense such as the AIM-9 Sidewinder missile, artillery munitions for High Mobility Artillery Rocket Systems (HIMARS), TOW anti-tank missiles, and 155mm and 105mm rounds.

The package marked the 48th time that the U.S. has used the presidential drawdown authority to provide Ukraine’s miliary with equipment from U.S. stockpiles, and it was the first since Congress excluded new aid for Ukraine in a stopgap spending bill passed last month to prevent a government shutdown.

Since Russia's large-scale invasion started in February 2022, the United States has provided approximately $44 billion in security assistance to Ukraine.

The Pentagon still has approximately $5 billion in congressionally authorized military aid to Ukraine.