SEOUL:

US Vice President Joe Biden visited the demilitarised buffer zone between South and North Korea with his granddaughter Finnegan yesterday as Seoul said it had extended its air defence zone to partially overlap with a similar zone declared by China two weeks, which has sharply raised regional tensions.

Beijing's unilateral declaration of an air defence identification zone in an area that includes islands at the heart of a territorial dispute with Japan has triggered protests from the US and its allies Japan and South Korea.