Thailand is claiming a new world record for the largest-ever aerobics work-out after nearly 47,000 people joined Prime Minister Thaksin Shinawatra for a one-hour session.

Organisers had hoped to attract up to 64,000, and blamed heavy rain for keeping many people away from the event in Bangkok.

Instructors led the class standing on raised platforms, with the capital's Grand Palace in the background.

Thaksin urged people to exercise and eat nutritious food

Setting a good example alongside the prime minister were Thai tennis star, Paradorn Srichaphan, and Public Health Minister Sudarat Keyuraphan.

Coverage of the exercises - part of a health awareness drive - was broadcast live on television countrywide enabling people all over the country to join in.

Apart from installing counting gates to record those entering for the session at the Sanam Luang royal grounds, officials said they also had photographs of the event taken from the air.

The event was part of the Power of Exercise Health Festival, organised by the Public Health Ministry to highlight the need for health diets and physical activity in preventing disease.

According to official statistics, Thailand's 62 million people made 92 million visits to hospital in 2000.

A fifth of the deaths recorded then were attributed to chronic illnesses including heart disease and high blood pressure.

Organisers are sending details of the aerobics session to the Guinness Book of Records for certification.

The previous world record for a mass aerobics event was held by Mexico where more than 38,000 people joined a work-out in the city of Guadalajara four years ago.