US Transportation Secretary Elaine Chao at a White House Lunar New Year reception on Jan 27, 2020. [Zhao Huanxin / China Daily]

US Transportation Secretary Elaine Chao announced her resignation on Thursday, ┬áthe first Cabinet member to leave in protest over what she said was “a traumatic and entirely avoidable event” that happened a day before, when supporters of President Donald Trump stormed the US Capitol.

Chao, the first Asian American woman to be appointed to a US president’s Cabinet in American history, said the violence “has deeply troubled me in a way that I simply cannot set aside”.

She said her resignation would take effect on Monday.

“We will help my announced successor, Mayor Pete Buttigieg, with taking on the responsibility of running this wonderful department,” she said in a letter made available to China Daily.

Chao, the wife of Senate Majority Leader Mitch McConnell, has served as transportation secretary since January 2017. She served as labor secretary for eight years between 2001 and 2009 under president George W. Bush.