The Kremlin accused U.S. President Joe Biden on Monday of raising Russia’s hostility in Ukraine’s nearly three-year war by apparently changing policy to allow Kiev to strike inside Russia using long-range missiles supplied by Washington.

Kremlin spokesman Dmitry Peskov said Biden’s decision was “a new round of escalation and a qualitative change in the situation from the perspective of U.S. involvement in the conflict.”

Russian President Vladimir Putin did not comment publicly, but Peskov referred reporters to a September statement by Putin in which he said allowing Ukraine to strike Russia would greatly increase the risk of conflict.

Putin said at the time that it would “dramatically change the nature of the conflict.” “It means NATO countries – the United States and European countries – are at war with Russia.

Peskov said the Western countries’ supply of long-range weapons also provides Kiev with strike services, “which fundamentally changes the way they participate in the conflict.”

The United States has so far allowed Ukraine to deploy short-range American weapons, such as the High Mobility Rocket Artillery System donated by the United States in the first months of the war, to strike Russian targets across the border from Ukraine’s Kharkiv region. These rockets have a range of about 80 kilometers, but Biden’s decision will allow the use of the Army Tactical Missile System (ATACMS), which can reach a range of about 300 kilometers.

Ukrainian President Volodymyr Zelenskyy has been lobbying Washington for months to allow the use of long-range rockets to strike military targets deep in Russia, saying that Russia’s stockpiled rocket arsenals and other weapons need to be hit and not used to strike Ukrainian cities and power grids.

Biden has so far not allowed the use of long-range missiles, fearing that this would escalate the war and tensions with the US-led NATO military alliance. But North Korea’s deployment of troops to fight alongside Moscow’s troops has shocked Washington.

The United States says the new missiles will first be used to strike Russian and North Korean forces trying to retake the Kursk region in southern Russia, which Ukraine seized in a surprise August raid and still holds.

The Army Tactical Missile System is a long-range guided missile produced by US aerospace and defense company Lockheed Martin that carries a 227kg fragmentation warhead and is fast and difficult to intercept.

The rockets are equipped with a special GPS and carry cluster bombs that release hundreds of bomblets instead of a single warhead when they explode in the air.

It was uncertain whether Biden’s decision to provide missiles and in what quantities would still be valid when President-elect Donald Trump takes office on January 20. Trump has expressed doubts about continued US support for Ukraine and refused to say in a political debate in September that he wanted Ukraine to win the war.

Trump said he would broker a ceasefire before taking office but did not say how he would achieve that goal.

Trump has not yet publicly commented on Biden’s decision to provide Ukraine with long-range missiles, but his son Donald Trump Jr. was quick to criticize it.

“It seems the military-industrial complex wants to ensure World War III before my father has a chance to create peace and save lives,” he said on social media.

Meanwhile, a Russian ballistic missile with cluster munitions hit a residential area in the northern Ukrainian city of Sumy late Sunday, killing 11 people, including two children, and injuring 84.

The southern Ukrainian city of Odessa was hit by another Russian missile attack on Monday, causing two apartment buildings to catch fire. At least eight people were killed and 18 were injured, including a child, Odessa Governor Oleh Kiper said.

Russia also carried out a large-scale bombing of Ukrainian power infrastructure earlier Sunday.

Zelensky said Ukraine and its allies should focus on “really forcing Russia to cease fire.”

“Today was one of the largest and most dangerous attacks launched by Russia in the entire war – 210 drones and missiles were launched simultaneously, including hypersonic and aeroballistic missiles,” Zelensky said in his evening speech.