Donald Trump swearing-in: Who will administer US President and VP oath to office?

US President-elect Donald Trump is set to take the oath of office on Monday in front of former presidents, key US officials and family members at the Capitol Hills of Washington DC.

Trump will swear-in as the 47th US President just after 12pm, marking the start of his second term in the Oval office.

Who will administer the oath?
As per tradition, US chief justice John Roberts will administer the oath of office to Trump in the inauguration ceremony although the US Constitution does not specify who must administer the oath.

Not every president, however, has been sworn in by the chief justice. In 1923, Vice President Calvin Coolidge took the oath from his father in after President Warren Harding died in office.

Lyndon Johnson was also sworn in by a federal judge on Air Force One after John F Kennedy was assassinated in 1963.

Vance to be sworn in first
Vice-President elect JD Vance will be sworn in before Donald Trump by justice Brett Kavanaugh. Trump tapped Kavanaugh for the Supreme Court in 2018.

The oath the vice-president elect will say is the same repeated by senators, House members and other federal employees, and has been in use since 1884. It states:

"I do solemnly swear (or affirm) that I will support and defend the Constitution of the United States against all enemies, foreign and domestic; that I will bear true faith and allegiance to the same; that I take this obligation freely, without any mental reservation or purpose of evasion; and that I will well and faithfully discharge the duties of the office on which I am about to enter: So help me God."

For the president, Article II, Section 1 of the Constitution requires he recite this oath:

"I do solemnly swear (or affirm) that I will faithfully execute the Office of President of the United States, and will to the best of my ability, preserve, protect and defend the Constitution of the United States."

US President-elect Donald Trump will take the oath of office inside Capitol Rotunda on Monday due to forecasts of extremely cold weather.

Alternative plans are necessary for the approximately 250,000 guests with tickets to view the inauguration from the Capitol grounds and the tens of thousands more expected in general admission areas or lining the inaugural parade route from the Capitol to the White House, according to a report by the Associated Press.