Vietnam said on Thursday it has appealed for international help in its desperate battle against a rapidly spreading outbreak of bird flu which has killed 13 people in the past month and may have crossed into Cambodia. The World Health Organisation (WHO), which fears the H5N1 virus could mutate into a form which could pass between humans and trigger a global pandemic that could kill millions, said Vietnam was at a critical juncture with the Tet Lunar New Year looming.

"We are afraid that this might be a watershed moment," WHO spokesman Peter Cordingley said in Manila.

Tet, during which much chicken is eaten, is being celebrated next week, but bird flu has already spread to half the country's 64 provinces since erupting again in December.

Copyright Reuters, 2005