By Jonathan Head BBC South East Asia correspondent

The 10 leaders of the Association of South East Asian Nations (Asean) have ended a summit meeting in Brunei with a pledge to improve economic ties, and co-operation in dealing with the threat from terrorism.

Asean also brought its three largest Asian neighbours - China, South Korea and Japan, into an attempt to expand co-operation beyond the 10 member states.

Asean members

Indonesia Thailand Philippines Brunei Cambodia Laos Malaysia Burma Singapore Vietnam

Asean has been struggling to present itself as a credible regional power-block ever since the financial crisis four years ago which crippled so many member-state's economies.

But the diversity of political cultures within the region make agreement on anything very hard to reach. This summit was no exception.

Terrorism

The leaders issued a statement on terrorism which excluded any mention of the issue which now divides South East Asia - Muslim states want an immediate halt to the US bombing in Afghanistan, but other states support it.

There were also declarations of support for Asean's goal of turning itself into a free-trade area, but the timetable now appears to have shifted from 2002 until 2010.

Summit played host to PMs from South Korea, Japan and China

In the current economic climate, governments here are unwilling to confront local vested interests who are against opening their borders to free trade.

One factor which could shake Asean out of its inertia is China, brought in as one of the three dialogue partners. With its own economy still growing fast, China's trade with South East Asia is worth $40bn dollars a year, and still rising.

A proposal to form an even greater free-trade area with China was floated at Brunei, although it's opposed by some Asean members.

The role Japan has played for the past 50 years as the driving force behind East Asia's prosperity is shrinking, along with its own economy, and it's China which is seen as the new power in the region.