U.S. national security adviser Robert C. O’Brien and Commerce Secretary Wilbur Ross will represent President Donald Trump at two regional summits in Thailand this weekend, the White House announced, a move that would widely be viewed in the region as a snub.

The decision to send O’Brien, who is a presidential adviser and not a member of Trump’s Cabinet, is likely to be viewed in Southeast Asia as sign of a lack of engagement in the region at a time when China’s influence and investments are quickly growing.

The announcement late Tuesday comes just days before Thailand is due to host the 10-nation Association of Southeast Asian Nations annual summit and the accompanying East Asia summit. The summits include sideline meetings that involve the U.S. and other major countries, including China, Russia, Japan and South Korea.

FILE - In this Oct. 21, 2019, file photo, Commerce Secretary Wilbur Ross listening to President Donald Trump speak during a Cabinet meeting in the Cabinet Room of the White House in Washington. The White House has announced that a national security adviser Robert C. O'Brien and Commerce Secretary Ross will attend two summits in Thailand. (AP Photo/Pablo Martinez Monsivais)
FILE – In this Oct. 21, 2019, file photo, Commerce Secretary Wilbur Ross listening to President Donald Trump speak during a Cabinet meeting in the Cabinet Room of the White House in Washington. The White House has announced that a national security adviser Robert C. O’Brien and Commerce Secretary Ross will attend two summits in Thailand. (AP Photo/Pablo Martinez Monsivais)

O’Brien recently took on his role after national security adviser John Bolton was ousted by Trump. He earlier was Trump’s chief hostage negotiator and is an established figure in Republican Party circles.

Ross is leading a Nov. 3-8 trade delegation to Bangkok and will speak at an Indo-Pacific Business Forum on Monday.

Last year, Vice President Mike Pence attended the summits in place of Trump. Trump attended the summits in 2017 and President Barack Obama attended most of the summits during his time in office, though he sent Secretary of State John Kerry to the 2013 summit in Brunei.

Soldiers jump from a helicopter during an emergency hostage situation exercise in Nonthaburi province, Thailand on Tuesday, Oct. 29, 2019. The 35th annual Association of Southeast Asian Nations (ASEAN) annual leaders' summit will be hosted in Thailand Nov. 2-4. (AP Photo/Sakchai Lalit)
Soldiers jump from a helicopter during an emergency hostage situation exercise in Nonthaburi province, Thailand on Tuesday, Oct. 29, 2019. The 35th annual Association of Southeast Asian Nations (ASEAN) annual leaders’ summit will be hosted in Thailand Nov. 2-4. (AP Photo/Sakchai Lalit)

China’s representative to the meetings will be its premier, Li Keqiang. Japanese Prime Minister Shinzo Abe is also attending.

ASEAN’s meetings focus on enhanced trade and security in a region of more than 630 million people. The grouping includes Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, the Philippines, Singapore, Thailand and Vietnam.

The Thai government has been ramping up security in advance of the summits and warning of road closures. Bangkok residents will get two days of “special holidays” to help alleviate traffic congestion for the summits, which are being held in a neighboring suburb.

Soldiers train in anti-terrorism drills in the Nonthaburi province, Thailand on Tuesday, Oct. 29, 2019. The 35th annual Association of Southeast Asian Nations (ASEAN) annual leaders' summit will be hosted in Thailand Nov. 2-4. (AP Photo/Sakchai Lalit)
Soldiers train in anti-terrorism drills in the Nonthaburi province, Thailand on Tuesday, Oct. 29, 2019. The 35th annual Association of Southeast Asian Nations (ASEAN) annual leaders’ summit will be hosted in Thailand Nov. 2-4. (AP Photo/Sakchai Lalit)

Regional trade ministers were hoping to make progress toward completing a long-awaited free trade agreement at the meetings. But officials are still working out technical details and rules on market access, competition and investment for the planned Regional Comprehensive Economic Partnership.

The countries negotiating the pact include ASEAN, and six of its dialogue partners: China, Japan, South Korea, Australia, New Zealand and India. It does not include the U.S.

If all join, it will be one of the biggest regional trading blocs, covering some 45% of the world’s population and about a third of global GDP, with projected trade of more than $10.3 trillion, almost 30% of the world total.