TOKYO (REUTERS) - A US Navy aircraft carrier, the Ronald Reagan, is conducting drills with a Japanese warship in waters around Okinawa south-west of the Korean peninsula, Japan's military said on Wednesday (Oct 11).

The exercise comes amid heightened tension with North Korea as the US holds air drills in the region with B1-B bombers flown from Guam.

The exercise with the Reagan strike group, which began on Saturday, involves vessels sailing from the Bashi Channel, which separates the Philippines and Taiwan, to seas around Japan's south-west island nearer to North Korea, Japan's Maritime Self Defence Force (JMSDF) said in a statement.

One Japanese destroyer, the Shimkaze, is accompanying the 100,000-ton Reagan, which is based in Japan, and its escort ships, the JMSDF said.