Prime Minister Hun Sen (second left) and Chinese Premier Wen Jiabao (centre) inspect an honour guard during the ASEAN and East Asia summits in Phnom Penh last month. Photograph: Heng Chivoan/Phnom Penh Post

In the days preceding the 20th ASEAN Summit in Phnom Penh in April – the first major event of Cambodia’s chairmanship – Chinese President Hu Jintao became his country’s first head of state to visit the Kingdom since 2000.

The enigmatic leader arrived bearing gifts – $40 million in grants, $30 million in loans and diplomatic compliments that included support for Cambodia’s UN Security Council bid and renewed talk of a $17 billion bilateral trade target by 2017.

Beneath the sweet-talking and financial splurging, Hu entered the Kingdom with another message: China wanted Cambodia to support its position on the resource-rich South China Sea.

Cambodia had been coy about whether the enduring and sometimes tempestuous dispute, which also involves Taiwan and ASEAN members Vietnam, the Philippines, Malaysia Indonesia and Brunei, would be on the summit’s agenda.

Either way, China wanted things not to move “too fast”, Jintao said, while the Philippines vowed to raise the issue in Phnom Penh whenever possible.

It was an issue that came to dominate Cambodia’s ASEAN chairmanship.

Armed soldiers patrolled the streets outside the Peace Palace in early April as Hun Sen, under the mantra of “one community, one destiny”, made an impassioned speech about regional unity to open the 20th ASEAN Summit.

Foreign ministers, greeted by dancers, singers and an orchestra, piled onto the stage to shake hands in front of a sea of cameras.

But the unity was short lived. By the end of day one, Philippines Foreign Secretary Albert del Rosario was publicly accusing Cambodia of defying the wishes of its regional counterparts and pushing for China to help ASEAN shape a draft code of conduct (COC) for the contested waters.

The extent to which the South China Sea proceeded to dominate discussions during the three-day summit came as no surprise to Carl Thayer, emeritus professor at the University of New South Wales.

“The fact the South China Sea is not for-mally on the agenda does not mean the issue will be ignored,” he said at the time. “ASEAN has a standard operating procedure to disguise controversial issues.”

At the conclusion of meetings, del Rosario said ASEAN states had agreed to decide the key elements before taking the COC to China – but no one else would confirm this.

In fact, simultaneous comments from Indonesian Foreign Minister Marty Natalegawa suggested room for Chinese involvement.

Hun Sen played down the division within ASEAN, but admitted a code of conduct remained only an eventual prospect – then turned his focus to his critics.

In a heated and bizarre closing address to the summit, the Prime Minister took aim at the myriad media reports accusing Cambodia of not only sidling up to China, but selling out to the superpower.

“Cambodia is not [being] bought by anyone,” he told a room full of hundreds of journalists.

The spectre of China loomed large again when the ASEAN Summit, including the 45th ASEAN Ministerial Meeting, returned in July.

An announcement from Kao Kim Hourn, secretary of state at the Ministry of Foreign Affairs, on the summit’s first day, mentioned China’s involvement.

“At the first meeting [on Sunday], they [senior officials] agreed that to work on the code of conduct . . . ASEAN will meet with China to discuss [it] from now on,” he said. “It is ASEAN and China.”

The words came just as a fleet of 30 Chinese fishing boats were entering a reef in the Spratly Islands, which are also claimed by the Philippines, Vietnam and Taiwan.

By the final day of the summit, del Rosario left the ASEAN Regional Forum so frustrated he refused to speak, but, as he exited, he handed reporters a statement slamming “aggressive infringement” by a “powerful country” into the disputed territory.

“If left unchecked, the increasing tension that is being generated in the process could further escalate into physical hostilities, which no one wants,” the statement read, accusing China, though not by name, of dupli-city, intimidation, threats and the use of force.

The presence of US Secretary of State Hillary Clinton was seen as the counterbalance to China’s influence in the dispute.

While China wanted bilateral talks with each individual nation claiming the waters, it was expected Clinton would push multilateral talks. Her rhetoric during a press conference lasting little more than 10 minutes was not as strong as some would have hoped, however.

The US had seen some “worrisome instances of economic coercion and the problematic use of military and government vessels in connection with disputes among fishermen”, she said, but made it clear she would not weigh into the dispute itself.

As her press conference ended, news was reverberating around the Peace Palace that ASEAN had failed to agree to a common statement, or joint communique, for the first time in its 45-year history.

“You ask the participants why it is they are not able to speak with one voice; whether it is the Philippines, whether it is the chair, Cambodia, whoever it is,” Natalegawa, Indonesia’s foreign minister, said.

“But I think it is utterly irresponsible that we cannot come up with a common statement on the South China Sea. This is a time when ASEAN should be seen to be acting as one.”

Surin Pitsuwan, the secretary-general of ASEAN, called it a minor hiccup, but it was clear to most that ASEAN was divided – and its credibility was under threat.

In a turbulent week that followed, Natalegawa jetted around Southeast Asia to unite members and salvage the bloc’s reputation.

 This “shuttle diplomacy” took him to Manila, Hanoi and Phnom Penh in the space of 36 hours – and later to Singapore – and resulted in the release of a statement on the South China Sea.

“The fact is, despite suggestions to the contrary . . . ASEAN remains united, ASEAN remains cohesive and, therefore, ASEAN remains able to fulfil its role in the central and driving seat in our region,” Natalegawa said while in Phnom Penh.

The 21st ASEAN Summit that followed in November promised all the big names. Like previous summits, traffic around the Peace Palace was diverted and schools were closed. The government vowed to sweep the streets clean of beggars and street vendors.

Evictees in a village next to Phnom Penh International airport painted huge SOS letters on their roofs to attract the attention of visiting US President Barack Obama and were arrested for it. Other protests were also shut down.

Russian President Vladimir Putin and UN Secretary-General Ban Ki-moon were missing, but China’s presence was again overt – on the eve of the summit it signed off on hundreds of millions of dollars in trade agreements with Cambodia and reiterated a desire to boost bilateral trade.

For a rare moment, however, it was agreement rather than disagreement that was making headlines.

The adoption of the long-awaited ASEAN Human Rights Declaration was met with opposition from civil society groups across the region that claimed the declaration would limit, rather than enhance, human rights.

And the timing couldn’t have been more trenchant. Obama’s visit, the first to Cambodia by a serving US president, came amid a storm of criticism directed at Hun Sen’s government for rights abuses, including the imprisonment of Beehive radio owner Mam Sonando.

According to US deputy national security adviser Ben Rhodes, the US president talked tough to Hun Sen behind closed doors.

“I would say the need for them to move towards elections that are fair and free, the need for an independent election commission associated with those elections, the need to allow for the release of political prisoners and for opposition parties to be able to operate [were all raised],” Rhodes said.

Prak Sakhon, Council of Ministers secretary and Hun Sen adviser, said the Prime Minister had told Obama the state of human rights in Cambodia had been exaggerated.

“The premier stressed there are no political prisoners in Cambodia, but politicians who had abused the law must stand trial,” he said.

November’s meeting again showed that it wouldn’t have been an ASEAN summit in Phnom Penh without the South China Sea dispute taking front and centre stage.

This time, Cambodia said regional leaders were in agreement not to “internationalise” disputes within the resource-rich sea – a day later the Philippines said no such agreement had been reached.

“This was not the understanding of both the Philippines and at least one other country,” del Rosario said.

Tensions simmered, but nothing came to boiling point. ASEAN released a statement, though not without Singapore pointing out that the initial draft had misquoted its leaders.

The South China Sea dispute – and not even the dispute itself, only questions of how to approach it – dominated discussions, divided ASEAN and ultimately defined Cambodia’s year as chair.

It remains to be seen how ASEAN’s “one community”, with special guests China and the US, fares when it travels next year to Brunei – one of the countries locked in the far-from-resolved dispute.