Sean O'Neill | |
|---|---|
 | |
| United States Ambassador to Thailand | |
| Assumed office February 11, 2026 [1] | |
| President | Donald Trump |
| Preceded by | Robert F. Godec |
| Personal details | |
| Nationality | American |
| Spouse | Sachiyo Kubo |
Sean Kotaro O'Neill is an American diplomat and the United States Ambassador to Thailand since February 2026. [2] [3] [4] O'Neill is a career member of the Senior Foreign Service,and he had served as Senior Bureau Official for the US State Department's Bureau of East Asian and Pacific Affairs. [2]
O'Neill previously served as United States Consul-General in Chiang Mai. [5]
On July 9,2025,President Donald Trump nominated O'Neill to be the next United States Ambassador to Thailand,succeeding Robert Godec. [6]
During his confirmation hearing,O'Neill criticized Thailand's border conflict with Cambodia,saying:
I think the first thing I would do is to point out to Thailand, which is one of our only treaty allies in Asia, that wars like this, conflicts like this, do nothing to help their people. [7]
O'Neill was confirmed by the Senate on October 7, 2025. [8] He was among a group of over 100 nominees confirmed with a simple majority vote of 51 to 47, including former US Ambassador Michael DeSombre as assistant secretary of state for East Asian and Pacific Affairs. [8]
O'Neill was sworn in on November 12, 2025 in the Franklin Room of the United States Department of State, in the presence of Assistant Secretary of State for East Asian and Pacific Affairs Michael Desombre and former ambassador Brian McFeeters. [4] He arrived in Bangkok on January 2026. He presented his credentials to King of Thailand Vajiralongkorn on February 11, 2026.
O'Neill is married to Sachiyo Kubo. [9]