USS Ronald Reagan (rear), a Nimitz-class nuclear-powered supercarrier, sails side-by-side with Japan Maritime Self-Defense Force's Hyuga-class helicopter destroyer Ise (DDH-182) during their joint military drill in the sea off Japan, in this photo released taken by Japan Maritime Self-Defense Force on September 14, 2017 and released on September 22, 2017. Picture taken September 14, 2017. Japan Maritime Self-Defense Force/HANDOUT via REUTERS

TOKYO (Reuters) - The U.S. Navy carrier Ronald Reagan is conducting drills with Japanese warships in seas south of the Korean peninsula, Japan’s military said on Friday, in a show of naval power as Pyongyang threatens further nuclear and missile tests.

The Reagan strike group will conduct a separate drill with the South Korean Navy in October, the defense ministry said in a statement distributed to South Korean lawmakers on Monday.

The 100,000-ton Reagan, which is based in Japan, and its escort ships have been holding drills with Japanese navy vessels since Sept 11 in waters south and west of Japan’s main islands, the Japan Maritime Self Defence Force said in a statement.

That exercise with the three Japanese warships, including two destroyers and one of the country’s two biggest helicopter carriers, the Ise, will run until Sept 28, it added.

The U.S. and regional allies are responding with military drills, including bomber and jet fighter flights near the Korean peninsula, as Pyongyang pursues its nuclear and missile programs, with an apparent hydrogen bomb test and two ballistic missile firings over Japan in recent weeks.

North Korea on Friday said it might test a hydrogen bomb over the Pacific Ocean after U.S. President Donald Trump vowed to destroy the country.