US Vice-President Mike Pence reiterated his country's commitment to the security of Japan on Tuesday, as North Korea intensified concerns over its weapons programme with a vow to launch missile tests "every week".
The North, which is intent on developing a nuclear-tipped ballistic missile capable of reaching the mainland United States, defied international pressure Sunday with a test that failed immediately after launch.
As fears grow that it may also be preparing for its sixth nuclear weapons test, Vice Foreign Minister Han Song-Ryol said that its programme would only escalate.
"We'll be conducting more missile tests on a weekly, monthly and yearly basis," Han told the BBC in an interview, threatening "all-out war" if the US took any action against it.
Arriving in Tokyo for talks with Japanese Prime Minister Shinzo Abe, Pence hailed the two countries' longstanding security ties.