US officials say President Joe Biden remains fully committed to the ASEAN region, even though he is not attending the leader-level meetings.
A State Department statement said Blinken would leave on Tuesday for the Laotian capital of Vientiane and stay there until Friday.
Blinken's subsequent schedule, after the White House announced that Biden was postponing a trip to Germany and Angola to handle preparations for Hurricane Milton and relief efforts after Hurricane Helene, was not immediately clear.
Tensions in the South China Sea and Myanmar's civil war will be on the agenda at ASEAN talks. (AP PHOTO)
Assistant Secretary of State for East Asian and Pacific Affairs Daniel Kritenbrink said he had no details to share about Blinken's plans for bilateral meetings in Vientiane, including any with China.
But a number of China-related issues would come up, including its "escalatory and irresponsible steps designed to coerce and pressure many of the South China Sea claimants".
On China's support for Russia over Ukraine, he added: "our concerns regarding China's strong support for the Russian defence industrial base, they remain, they are ongoing, and I would say they are growing".
Kritenbrink said Washington remained "deeply concerned" about plans by Myanmar's military government to hold elections, and these should not be held until there was genuine peace and reconciliation in the country.
He said there has been "virtually zero progress" in efforts to press the junta to reduce violence, release political prisoners and engage with the democratic opposition.
"The secretary will continue to emphasise to partners in the region that we must keep up pressure on the regime," he said.
"We ... fear that premature elections would be neither representative nor inclusive, and perhaps ... would likely only generate more violence and prolong the ongoing crisis," he said.
