Russia on Monday warned the United States against sending more arms to Ukraine.

The country’s ambassador to Washington warned that large Western deliveries of weapons were inflaming the conflict and would lead to more losses.

Russia’s Feb. 24 invasion of Ukraine has killed thousands of people, displaced millions more and raised fears of a wider confrontation between Russia and the U.S., by far the world’s two biggest nuclear powers.

The U.S. has ruled out sending its own or NATO forces to Ukraine but Washington and its European allies have supplied weapons to Kyiv such as drones, Howitzer heavy artillery, anti-aircraft Stinger and anti-tank Javelin missiles.

Anatoly Antonov, Russia’s ambassador to the U.S., said such arms deliveries were aimed at weakening Russia but that they were escalating the conflict in Ukraine, while undermining efforts to reach some sort of peace agreement.

“What the Americans are doing is pouring oil on the flames.

“I see only an attempt to raise the stakes, to aggravate the situation, to see more losses,” Antonov told the Rossiya 24 TV channel.