Top Asean leaders, including Prime Minister Lee Hsien Loong, did not attend yesterday's annual summit with the United States, with the majority opting to send their respective foreign ministers instead.
PM Lee met his Australian counterpart Scott Morrison at the time.
The Asean-US Summit was attended by only three leaders from the region - Thailand's Prime Minister Prayut Chan-o-cha, Vietnam's Prime Minister Nguyen Xuan Phuc, and Laos' Prime Minister Thongloun Sisoulith. Thailand is hosting this year's Asean Summit and passes the chairmanship to Vietnam next year. Laos is the current country coordinator for Asean-US relations.
Washington sent a relatively low-level delegation to this year's Asean Summit, a decision that was widely perceived as a snub given that other top leaders were present. These included Prime Minister Narendra Modi from India and Premier Li Keqiang from China.
This year, US President Donald Trump sent as his special envoy National Security Adviser Robert O'Brien, along with Commerce Secretary Wilbur Ross.
At the Asean-US Summit, Mr O'Brien read out a letter from Mr Trump in which the US President invited Asean leaders to the United States for a "special summit" in the first quarter of next year.
"This will provide an excellent opportunity for us to broaden and deepen our cooperation on matters of great importance to the nearly one billion people the US and the Asean nations have the privilege to represent," the letter read.
In his letter, Mr Trump also assured leaders that his special envoy was "well-placed to speak authoritatively" on issues that were of interest to both the US and Asean.
In his speech, Mr O'Brien assured regional leaders of the "rock-solid American commitment in word and deed to our friends, allies and partners in Asean". He also had strong words for China's behaviour in the South China Sea, which he called "intimidation".
"These tactics go against the rules of respect, fairness and international law. The region has no interest in a new imperial era where a big country can rule others on the theory that might makes right."
He stressed that the US plays an important role in helping Asean nations uphold sovereignty through efforts such as security assistance and joint naval exercises.
Speaking to reporters after the summit, Mr O'Brien added: "I think the United States was treated very well by the Asean partners and I was treated very generously."
Both Mr Trump and Vice-President Mike Pence were reportedly unable to attend the summit because they were "very engaged in campaigning" for a string of governors' races. This is the second year in a row that Mr Trump has skipped the Asean Summit. In contrast, his predecessor Barack Obama attended every Asean-US Summit and East Asia Summit from 2011, with the exception of 2013 due to a US government shutdown.
The Asean leaders' decision to send their respective foreign ministers to the Asean-US Summit could be interpreted as "a strong rebuke of US inattentiveness to the region", noted Dr Tang Siew Mun, who heads the Asean Studies Centre at ISEAS-Yusof Ishak Institute.
He said the invitation to the "special summit" would normally be seen positively, but took on a different meaning in this context.
"In the light of the diplomatic fiasco in Bangkok, the invitation may be viewed as a 'consolation prize' for Trump's no-show at the Asean-US Summit and East Asia Summit."
From a practical standpoint, the logistics of organising this summit at such short notice would also have to be worked out, given that such meetings are typically planned months in advance.
"Besides logistics issues and canvassing the availability of the Asean leaders, both sides have to work out an agenda and agree on the deliverables of the summit," Dr Tang said. With Mr Trump "fighting impeachment ... in the coming months, how much time and attention can he and his senior staffers devote" to the proposed special summit?