Vice President-elect Mike Pence said on Sunday that he was disappointed by a black civil rights activist and politician's questioning of Donald Trump's legitimacy as president of the United States and his decision to boycott Friday's inauguration.

Rep. John Lewis, a Georgia Democrat, said on Friday he thought hacking by Russians had helped Trump, a Republican, get elected in November. Lewis said he does not plan to attend Trump's Jan. 20 inauguration, the first time he would miss such an event since being elected to the House in 1986.

"We honor the sacrifice that he made," Pence said on CBS' "Face the Nation" program. "For someone of his stature not just in the civil rights movement but in voting rights to make a comment that he did not consider Donald Trump to be a legitimate president I think is deeply disappointing. I hope he reconsiders both statements."

Pence said he had attended both of President Barack Obama's inaugurations. He said at a time when the country was facing challenges both at home and abroad, Americans should look for ways to come together and work together.

Similar sentiments were echoed by incoming White House chief of staff Reince Priebus. Speaking on ABC's "This Week" program, Priebus said Lewis' comments, given his position in society, were irresponsible and disappointing.

"We need folks like John Lewis, and others who I think have been champions of voter rights, actually recognize the fact that Donald Trump was duly elected," said Priebus. "I think putting the United States down across the world is not something that a responsible person does."

Both Pence and Priebus defended Trump's hard hitting response on Twitter on Saturday that Lewis "should spend more time on fixing and helping his district, which is in horrible shape and falling apart (not to mention crime infested)," instead of complaining about the Nov. 8 election results.

"This man won in an electoral landslide. And to question the legitimacy of the next United States president, you know, and you're worried about a Twitter that says, hey, why don't you get back to work instead of questioning my legitimacy? Too bad," said Priebus.

The 76-year-old Lewis, who has been a civil rights leader for more than half a century, was beaten by police during a march he helped lead in 1965 in Selma, Alabama, drawing attention to hurdles preventing blacks from voting. He protested alongside leader Martin Luther King Jr. that day and on other occasions.

At least 10 other Democratic U.S. politicians have also said they plan to skip the inauguration.