North Korea launched a long-range ballistic missile into the sea off Japan's west coast on Saturday afternoon after warning of a strong response to upcoming military drills by South Korea and the United States.

ICBM is fired the day before in a "sudden launching drill" that confirmed its readiness for a "mobile and mighty counterattack" against hostile forces.

Japan’s Defense Ministry characterized the weapon as an “ICBM-class” missile, noting it traveled for more than an hour before splashing into waters some 200 kilometers west of Hokkaido prefecture’s Oshima-Oshima Island at about 6:27 p.m. The Tokyo government has lodged an official protest against Pyongyang through its embassy in Beijing, Kyodo News reported.

Saturday’s missile launch follows a warning by North Korea’s Foreign Ministry issued Friday that U.S.-planned actions, including what it claimed were 20 joint military exercises with South Korea this year, would again plunge the Korean Peninsula “into the grave vortex of escalating tension.”

Last week, the US called for more UN sanctions on North Korea over its ballistic missile launches, but China and Russia vetoed the suggestion, publicly splitting the UN Security Council on North Korea for the first time since it started punishing it in 2006 when North Korea conducted its first nuclear test.

North Korea’s last tests were on May 25, when it launched three missiles after US President Joe Biden ended an Asia trip where he agreed to new measures to deter the nuclear-armed state.

The first missile appeared to be the North’s largest ICBM, the Hwasong-17, while a second unspecified missile appeared to have failed mid-flight, South Korean officials said at the time. The third missile was a short-range ballistic missile (SRBM).

On Saturday South Korean and American ships concluded three days of drills in international waters off the Japanese island of Okinawa, including air defense, anti-ship, anti-submarine, and maritime interdiction operations, South Korea’s Joint Chiefs of Staff said.