BANDAR SERI BEGAWAN, Brunei - After the US president's no-show at a pair of Asia-Pacific summits, eyebrows are being raised over Russian leader Vladimir Putin's decision to also skip one of the gatherings.
Despite coming to the region for an economic meeting in Indonesia earlier this week, Mr Putin has passed on a subsequent East Asia summit in the sultanate of Brunei set for Friday.
It marks the third straight year that Moscow has sent a stand-in to a gathering that Russia had lobbied hard to join in 2011, raising questions over Moscow's level of commitment to the East Asia bloc.
Russia had promised "to be represented at the highest level", said Dr Surin Pitsuwan, former secretary general of the Association of Southeast Asian Nations (ASEAN), annual host of the East Asia summit.
"For some reason or another they have not been. That is disappointing."
US President Barack Obama cancelled a visit to Asia, including the twin leaders' meetings, due to the US government shutdown, casting doubt over his administration's planned pivot to the region.
Brunei organisers of Friday's summit - a group of 18 nations, including Southeast Asian countries, the United States, China and Russia - said Moscow also had informed them a week ago that Mr Putin would not be coming.
He is instead represented in Brunei by his foreign minister Sergei Lavrov.
The United States and Russia first joined the 16-nation East Asian bloc, which centres on ASEAN, in 2011 in what analysts saw as a potential check on Chinese influence in the region.
But it is becoming increasingly clear that Russia's trade and other ties with the ASEAN bloc are too small to rate high-level interest from Moscow, said a Southeast Asian diplomat who spoke on condition of anonymity.
"It (Putin's absence) just reflects how Russia looks at ASEAN - that it doesn't give much weight to ASEAN," said the diplomat, noting Russia has no direct stake in hot-button issues in the region such as overlapping claims in the strategic South China Sea.
"It does seem that Russia has given more premium to its relations with the Apec grouping."
Apec refers to the Asia-Pacific Economic Cooperation bloc spanning the region.
Just days ago at the Apec summit in Bali, Mr Putin touted the importance of Russia's involvement in supplying energy to growing Asian markets.
A Kremlin spokesman denied that Russia had lost interest in ASEAN and the East Asia summit, but added: "Unfortunately, he (Putin) cannot attend every summit. There is a degree of priority for everything."
But Mr Fyodor Lukyanov, chairman of the Kremlin-linked Council on Foreign and Defence Policy, said: "Putin has simply nothing to offer this summit."
"You need a really strong agenda for the president to go to such an event, especially when Russia is not a member," he said.
"But there is no such agenda, so we decided that there was no point in going there as tourists."