LIAM COCHRANE, REPORTER: Cambodia was hoping it would end its turn as chair of ASEAN (Association of South-East Asian Nations) on a high. The guest list was impressive, with world leaders gathering for talks and the usual colourful dress ups. But it wasn't only the colours that clashed.
The Philippines confronted Cambodia over claims that ASEAN was united over disputes in the South China Sea.
ROS CHANTRABOT, ADVISER TO CAMBODIAN PRIME MINISTER (translation): Most ASEAN members, us included, have agreed not to talk about the South China Sea issue at international events like this.
LIAM COCHRANE: Most may have agreed but not all.
Philippines president, Benigno Aquino, interrupted Cambodia's Hun Sen to raise the objections of his country and one other, believed to be Vietnam.
There was no consensus, he said, insisting the Philippines would pursue its national interests if necessary outside the ASEAN model.
It was a loss of face for Cambodia, a close ally of China, which claims most of the South China Sea.
DR SURIN PITSUWAN, ASEAN SECRETARY GENERAL: We are not going to allow the issue to cloud or to affect other pursuits that we're doing together here with our dialogue partners.
LIAM COCHRANE: Those in the region believe the issue is serious enough to warrant discussions within the East Asia Summit, the grouping that involves ASEAN plus China, Russia, the US and Australia.
The United States and Australia are in lockstep on this issue, both pushing for a legally binding code of conduct to maintain peace in the South China Sea.
JULIA GILLARD, AUSTRALIAN PRIME MINISTER: We do believe that a code of conduct would assist with making sure that any, you know, issues in the South China Sea, any conduct there, could be managed in accordance with the code. That is, that the rules and manner of responses would be predictable and knowable.
LIAM COCHRANE: Regardless of whether ASEAN can paper over its differences this is time around, the rifts that have emerged during Cambodia's turn as chair unsettled its members.
After this summit the chair will pass to Brunei, a claimant country and the secretary general will be from Vietnam, another nation in dispute with China. This could shift the way ASEAN deals with the South China Sea issue.
While questions of consensus dominated the ASEAN meetings, the East Asia Summit wasn't just about security. In fact, on the sidelines of ASEAN negotiations began on a regional Free Trade Agreement that would cover a third of the world's exports.
CRAIG EMERSON, AUSTRALIAN TRADE MINISTER: The goal of both the Trans Pacific Partnership and the Regional Comprehensive Economic Partnership is to realise the vision of APEC (Asia-Pacific Economic Cooperation) for a free trade area for Asia and the Pacific.
Now, we now look like we're going to have two pathways to the one destination - a free trade area of Asia and the Pacific.
LIAM COCHRANE: Others see the two similar free trade pacts as competing: one including the US, the other leaving it out.
On the sidelines of the summits bilateral meetings offered the chance for less diplomatic encounters.
In contrast to the encouragement Barack Obama offered Burma, the meeting with Cambodia reportedly became tense when the US president raised human rights, violent land evictions and political prisoners.
PRAK SOKHAN, CAMBODIAN SECRETARY OF STATE (translation): During the meeting, US president Obama also raised the concerns of the US about Cambodian human rights issues, the process of democracy, and next year's general election.
LIAM COCHRANE: The criticism went both ways. Cambodia earlier accused the US of acting on behalf of the opposition, which is united under the self exiled leader Sam Rainsy.
In a clumsy diplomatic response, Cambodia insisted it was not a banana republic, when in fact no one had suggested it was.
Add to that suppression of peaceful protests before and during the summits, taking the shine off what should have been a moment of triumph for Cambodia.