Deputy national security adviser Matt Pottinger is the latest in a series of resignations of senior White House administration staff, according to CNN.
Mr Pottinger had reportedly intended to resign on election day, but was persuaded to stay on by national security adviser Robert O'Brien.
Mr O'Brien, who is also rumoured to be considering resignation, has signalled his unhappiness over recent violence on Capitol Hill.
Expressing outrage on social media following the violence on Wednesday evening, Mr O'Brien wrote: "What the mob did to our Senate Chamber today was an utter disgrace."
Mr O'Brien later retweeted a post by conservative commentator Andy Ngo, who called for the arrest of "Trump supporters" vandalising parts of the Capitol building.
This follows a growing chorus of dissent among President Donald Trump's most fervent supporters, angered by what they see as incitement by the president, who continues to insist the US elections were fraudulently 'stolen' by president-elect Joe Biden.
Late on Wednesday, two top aides to US first lady Melania Trump also resigned after the Capitol Hill riots.
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An explosion caused by a police munition is seen while supporters of former president Donald Trump gather in front of the US Capitol Building in Washington, US, January 6, 2021. Reuters -
A supporter of US President Donald J. Trump sits on the desk of US House Speaker Nancy Pelosi, after supporters of US President Donald J. Trump breached the US Capitol security in Washington. EPA -
Police detain a person as supporters of US President Donald Trump protest outside the US Capitol. AFP -
Protesters enter the US Capitol Building. AFP -
A protester holds a Trump flag inside the US Capitol Building near the Senate Chamber. AFP -
US Capitol police officers point their guns at a door that was vandalized in the House Chamber during a joint session of Congress. AFP -
Members of congress run for cover as protesters try to enter the House Chamber during a joint session of Congress. AFP -
Congress staffers barricade themselves after Trump supporters stormed inside the US Capitol. AFP -
Congress staffers barricade themselves after Trump supporters stormed inside the US Capitol. AFP -
Congress staffers hold up their hands while Capitol Police Swat teams check everyone in the room as they secure the floor of Trump supporters. AFP -
US Capitol Police stand detain protesters outside of the House Chamber during a joint session of Congress. AFP -
A supporter of US President Donald Trump sits at a desk after invading the Capitol Building. AFP -
A protester sits in the Senate Chamber. AFP -
Pro-Trump protesters tear down a barricade as they clash with Capitol police during a rally to contest the certification of the 2020 US presidential election results by the US Congress. Reuters -
Police hold back supporters of US President Donald Trump as they gather outside the US Capitol's Rotunda. AFP -
Supporters of US President Donald Trump enter the US Capitol's Rotunda. AFP -
A protester is seen hanging from the balcony in the Senate Chamber. AFP -
Riot police prepare to move demonstrators away from the US Capitol. AFP -
Trump supporters clash with police and security forces as they storm the US Capitol. AFP -
Trump supporters clash with police and security forces, as they storm the US Capitol. AFP -
A supporter of US President Donald Trump wears a gas mask as he protests after storming the US Capitol. AFP -
Pro-Trump supporters storm the US Capitol following a rally. AFP -
Supporters of US President Donald Trump protest inside the US Capitol. AFP -
US President Donald Trump is seen on TV from a video message released on Twitter addressing rioters at the US Capitol, in the Brady Briefing Room at the White House in Washington, DC. AFP -
Trump supporters clash with police and security forces as they storm the US Capitol in Washington, DC. AFP -
Supporters of US President Donald Trump protest in the US Capitol Rotunda. AFP -
Paramedics perform cardiopulmonary resuscitation on a patient. AFP -
A wounded protester is carried on barricade as demonstrators breach the US Capital building grounds. Bloomberg -
US Vice President Mike Pence and House Speaker Nancy Pelosi preside over a joint session of Congress to certify the 2020 Electoral College results after supporters of President Donald Trump stormed the Capitol earlier in the day on Capitol Hill in Washington, DC. EPA -
Rep. Andy Kim, D-N.J., cleans up debris and personal belongings strewn across the floor of the Rotunda in the early morning hours of the morning, after protesters stormed the Capitol in Washington. AP
Stephanie Grisham resigned as chief of staff to the first lady, the White House social secretary, Rickie Niceta, also resigned, as did a deputy White House press secretary, Sarah Matthews.
"It has been an honour to serve the country in the White House. I am very proud to have been a part of Mrs Trump’s mission to help children everywhere and proud of the many accomplishments of this administration," said Mr Grisham in a statement.
Ms Grisham, who spent a year as White House press secretary before becoming chief of staff to the first lady, did not say whether her resignation was in reaction to the violence in the nation's capital, but a source familiar with her decision said the violence was the last straw for her.
Mr O'Brien said in a statement earlier Wednesday: "I just spoke with Vice President Pence. I am proud to serve with him."
There was also chatter inside the White House that deputy chief of staff Chris Liddell might resign, a source said.
The mounting anger among those close to Mr Trump began after the president continued to push unfounded claims that the US election was marred by large-scale fraud. On Thursday, Senator Lyndsey Graham said that Mr Trump's continued campaign to overturn results had pushed him to part ways with the president.
"Trump and I, we had a hell of a journey. I hate it being this way … all I can say is count me out. Enough is enough. I tried to be helpful," he remarked.
Injuries were reported and one woman was killed in the melee at the Capitol, as Trump supporters responded to the president's call to protest his loss in November's presidential election to Democrat Joe Biden. Mr Trump has repeatedly and baselessly claimed the election was marred by fraudulent voting.
