The World Health Organisation (WHO) has declared Thailand and 10 other countries in Southeast Asia polio-free, Thai News Agency (TNA) reported.

The other countries are Bangladesh, Bhutan, North Korea, India, Indonesia, Maldives, Myanmar, Nepal, Sri Lanka and Timor-Leste.

No polio cases have been reported in Thailand and the 10 countries for three consecutive years.

Deputy Permanent-Secretary for Public Health Dr. Amnuay Kajina told reporters on Friday that the last polio case in Thailand was reported in 1997.

The Geneva-based United Nations agency has set a target that all economies worldwide become polio-free by 2018.

Three out of six regions have earlier been declared polio-free by WHO -- the Americas, European and Western Pacific regions.