The leaders of the five member countries of the south East Asian Nations Organisation (ASEAN) signed a treaty increasing co-operation in Bali, Indonesia, on Wednesday (24 February).

The treaty sets out to improve economic, political and social co-operation and includes a method for settling disputes.

The leaders who signed the treaty were President Ferdinand Marcos of the Philippines, President Suharto of Indonesia, Prime Minister Lee Kuan Yew of Singapore, President Datuk Hussein Onn of Malaysia and Prime Minister Kukrit Framoj of Thailand.

The treaty resulted from a series of discussions between the leaders which cleared a number or disagreements on key points. It is seen as a way of meeting new challenges in the area following last year's Communist victories in Indochina. But an article of the treaty opened the way for Communist and other countries to join the association which was founded by the current members sight and a half years ago.

Observers say the summit meeting made no attempt to form a military impact which could he construed as "ganging up" on other countries in the region.

They also agreed that the best defence against rebel movements emerging was a drive to improve the standard of living of their people through increased economic co-operation and national resilience.