The U.S. has delivered all the previously pledged 31 Abrams tanks to Ukraine, U.S. Army Europe and Africa Command's spokesperson Martin O'Donnell told the Voice of America.
The Ukrainian soldiers who trained on Abrams with U.S. troops in Germany have also returned to Ukraine, along with ammunition and spare tank parts, according to O'Donnell.
"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," the U.S. military official said, as cited by the Voice of America.
"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."
On Sept. 25, President Volodymyr Zelensky confirmed that the first U.S.-made Abrams tanks had arrived in Ukraine. He didn't specify how many vehicles had been delivered in the first batch.
U.S. President Joe Biden announced the decision to send 31 M1 Abrams tanks, a force equivalent to one Ukrainian battalion, to Ukraine in January, just as other Western partners pledged their own advanced armor, such as Leopard 2 or Challenger 2 tanks.
The tanks, which offer greater mobility and firepower than Soviet battle tanks, are expected to support Ukraine's defensive and offensive efforts.