▲ Virginia-class US nuclear submarine that entered the port of Busan in 2017

Amid the ongoing confrontation between Russia and the West over Ukraine, the Russian Ministry of Defense has announced that it has expelled a U.S. nuclear submarine that invaded Pacific waters.

The US countered that there was no such fact.

The Russian Ministry of Defense claims it has detected a US Virginia-class submarine in Russian territorial waters near Urup Island in the Kuril Islands.

Virginia-class submarines are the U.S. Navy's first nuclear-powered attack submarines, commissioned in 2004.

Russia's defense ministry said its Pacific Fleet had demanded that its Pacific Fleet detect US submarines during training and immediately float above sea level, but the submarines ignored them.

According to the Ministry of National Defense, when a Russian destroyer took an 'appropriate response' in accordance with the territorial waters protection guidelines, the US submarine quickly left Russian territorial waters, the Ministry of National Defense added.

In a statement that followed, the Ministry of National Defense said, "A military officer from the US embassy in Moscow has been summoned in connection with the invasion of Russian territorial waters by a US submarine."

The US completely denied this explanation and emphasized the principle of operating US ships and aircraft.

U.S. spokeswoman Kyle Reigns said in a statement that "Russian claims that U.S. forces were operating in Russian territorial waters are not true."

"We will not comment on the exact location of the US submarine, but we are flying and sailing safely in the high seas," Reigns said.