This file photo dated April 29, 2022, shows airmen with the 436th Aerial Port Squadron use a forklift to move 155 mm shells ultimately bound for Ukraine, at Dover Air Force Base, Del. (PHOTO / AP)

MOSCOW — Russian Ambassador to the United States Anatoly Antonov on Tuesday condemned the US government's decision to supply Ukraine with ATACMS long-range missiles, calling it a grave mistake that will have serious consequences.

"The White House's decision to send long-range missiles to the Ukrainians is a gross error. The consequences of this step, which was deliberately hidden from the public, will be very serious. Washington is consistently pursuing a line of completely severing bilateral relations," said Antonov.

White House National Security Council confirmed on Tuesday that the United States transferred the missile system to Ukraine

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ATACMS, or Army Tactical Missile System, is a tactical ballistic missile manufactured by the US defense company Lockheed Martin. It has a range of up to 190 miles (about 300 km), which means it can hit targets inside Russia.

"We have repeatedly warned the (US) administration against rash steps. We explained that pumping weapons to the Kiev regime seriously undermines strategic and regional security. The United States continues to push for a direct confrontation between NATO and Russia," said Antonov.

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White House National Security Council Spokesperson Adrienne Watson confirmed on Tuesday that the United States transferred the missile system to Ukraine.