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By David Shepardson
WASHINGTON, Jan 7 (Reuters) - U.S. Transportation Secretary Elaine Chao said on Thursday she would resign, citing the storming of the U.S. Capitol by violent supporters of President Donald Trump.
Chao, the wife of Republican Senate Majority Leader Mitch McConnell, was the first Cabinet secretary to announce her departure after the incident on Wednesday. Many lower-level administration officials have announced they would resign, including several White House aides.
Chao said her resignation would take effect on Monday, just nine days before Trump leaves office. She said in an email to staff that the Capitol attack "has deeply troubled me in a way that I simply cannot set aside."
She made the announcement a day after McConnell condemned the actions of the mob that descended on the Capitol and the effort by some Republican lawmakers to block formal congressional certification of Democratic President-elect Joe Biden's Nov. 3 election victory.
Trump has claimed without evidence that the election was marred by widespread fraud and sought unsuccessfully to overturn his loss.
"We will help my announced successor Mayor Pete Buttigieg," said Chao, who has led the department for four years. She was labor secretary and deputy transportation secretary under prior Republican presidents.
She had said in a Dec. 31 Reuters interview that she planned to remain on the job through Jan. 20 when Biden takes office.
During her four-year tenure, she has overseen a number of key rulemakings including a joint effort with the Environmental Protection Agency to roll back the Obama-era fuel economy standards as well as the Federal Aviation Administration's 20-month grounding of the Boeing 737 MAX after two fatal crashes in Indonesia and Ethiopia.
Chao has also headed the department's response to the COVID-19 pandemic and was an advocate for giving airlines tens of billions of dollars in payroll assistance to keep thousands of workers on the payroll. But the department came under criticism for not mandating facial coverings in interstate travel including on airplanes.
The department has also taken steps to eliminate barriers to deployment of self-driving, while critics - including the National Transportation Safety Board - say regulators have failed to ensure the safety of autonomous vehicles being tested.
In the December interview, Chao acknowledged she had been "fairly quiet on the media front."
She said she had focused on trying to boost innovative technologies like self-driving vehicles, commercial space and drones "by eliminating unnecessary obstacles."
"We are going to be remembered for having laid the foundation during a transformational time in transportation technologies and preparing the way for the transportation system of the future," Chao added.
(Reporting by David Shepardson; Editing by Alistair Bell and Peter Cooney)
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