US Secretary of State John Kerry. Reuters/James Lawler Duggan Outgoing Secretary of State John Kerry will not attend President-elect Donald Trump's inauguration on Friday, a State Department spokesperson confirmed on Wednesday.

The spokesperson would not elaborate on why Kerry, who was in Davos, Switzerland, for the World Economic Forum this week, won't be attending the inauguration.

The announcement comes after more than 50 Democratic lawmakers said they would follow Rep. John Lewis' lead and boycott the inauguration.

Lewis, a Georgia Democrat, told MSNBC last week that he did not consider Trump to be a "legitimate president" because he thought Russian hacking helped get him elected in November. Lewis also skipped George W. Bush's first inauguration in 2000.

Kerry joked during a discussion at the WEF on Tuesday that Trump may not serve his full term in office and explained why he thought a Trump administration could not unilaterally pull out of the multinational nuclear deal with Iran.

Pulling out of the deal "will hurt for the endurance of a year, two years, whatever — while the administration is still there," Kerry said, drawing laughter from the crowd in Davos.

A senior State Department official told Fox News: "It is not uncommon at all for the outgoing Cabinet officials not to attend. As you know, as of noon, they will no longer be in office."