North Korea says it is ready to sink a US aircraft carrier to demonstrate its military might, as two Japanese navy ships joined a US carrier group for exercises in the western Pacific.
US President Donald Trump ordered the USS Carl Vinson carrier strike group to sail to waters off the Korean peninsula in response to rising tension over the North's nuclear and missile tests, and its threats to attack the United States and its Asian allies, including Australia.
The United States has not specified where the carrier strike group is as it approaches the area.
US Vice President Mike Pence said in Sydney on Saturday it would arrive "within days" but gave no other details.
North Korea remained defiant.
"Our revolutionary forces are combat-ready to sink a US nuclear powered aircraft carrier with a single strike," the Rodong Sinmun, the newspaper of the North's ruling Workers' Party, said.
The paper likened the aircraft carrier to a "gross animal" and said a strike on it would be "an actual example to show our military's force".
The commentary was carried on page three of the newspaper, after a two-page feature about leader Kim Jong Un inspecting a pig farm.
North Korea will mark the 85th anniversary of the foundation of its Korean People's Army on Tuesday.
It has in the past marked important anniversaries with tests of its weapons.
North Korea has conducted five nuclear tests, two of them last year, and is working to develop nuclear-tipped missiles that can reach the United States.
North Korea says its nuclear program is for self-defence and has warned the United States of a nuclear attack in response to any aggression.
It has threatened to lay waste to South Korea and Japan, and also warned Australia about a nuclear attack if it continues to "blindly" follow the US.
The two Japanese warships, the Samidare and Ashigara, left western Japan on Friday to join the Carl Vinson and will "practice a variety of tactics" with the US strike group, the Japan Maritime Self Defence Force said.
The Japanese force did not specify where the exercises were taking place but by Sunday the destroyers could have reached an area 2,500 km south of Japan, which would be waters east of the Philippines.
From there, it could take three days to reach waters off the Korean peninsula.