LONDON - US Secretary of State John Kerry was headed for South Korea Thursday on his maiden trip to Asia in a show of American support for regional allies as tensions soar over a feared new missile test by the North.

The volatile situation on the Korean peninsula fuelled by a series of bellicose statements by Pyongyang was one of the global crises crowding the agenda for Kerry's two-day talks in London with G8 foreign ministers.

North Korea has threatened nuclear strikes against the United States and South Korea, and observers expect a missile launch could happen at any time.