Days before taking office, President-elect Donald Trump attempted to navigate the fallout of his flap with a civil rights leader and colleague of Dr. Martin Luther King Jr.

On Monday Trump met with one of King's sons on the holiday marking the life of the slain American icon just days after the president-elect attacked Rep. John Lewis of Georgia on Twitter. Lewis and the elder King were among the Big Six leaders of the civil rights movement of the 1960s.

Trump accused Lewis for being "all talk" after Lewis questioned the legitimacy of Trump's election. The president-elect also advised the veteran congressman to pay more attention to his "crime ridden" Atlanta-area district.

Trump's comments drew widespread criticism and have done little to reassure those uneasy about the transition from the nation's first black president to a president-elect still struggling to connect with most nonwhite voters.

Martin Luther King III downplayed the slight, saying that "in the heat of emotion a lot of things get said on both sides."

King, who said he pressed Trump on the need for voting reform to increase participation, deemed the meeting "constructive." King said that while he disagreed with the president-elect's comments, he believed "at some point in this nation we've got to move forward."

"He said that he is going to represent all Americans. He said that over and over again," King told reporters in the lobby of Trump Tower after the nearly hour-long meeting. "I believe that's his intent, but I think we also have to consistently engage with pressure, public pressure. It doesn't happen automatically."

Trump, who struggled for support from minority voters on Election Day, briefly joined King in the lobby but ignored reporters' shouted questions about his comments about Lewis.

Lewis had suggested that Trump's November victory was delegitimized due to Russian interference and said he would boycott Friday's Inauguration. More than two dozen Democratic members of Congress have said they will sit out the Trump ceremony.

Among them is Tennessee Rep. Steve Cohen, who said Monday that "this president 'semi-elect' does not deserve to be president of the United States. He has not exhibited the characteristics or the values that we hold dear."

The Martin Luther King holiday is meant to honor community service and volunteerism, and many Americans, including President Barack Obama, spend part of the day doing a service project of some kind. Trump, who cancelled a planned trip to Washington, spent the day inside the Manhattan skyscraper that bears his name.

Hours before her brother met with Trump, King's daughter encouraged 2,000 people at her father's Atlanta church to work for his vision of love and justice "no matter who is in the White House".

Speaking at Ebenezer Baptist Church, Bernice King avoided a detailed critique of Trump, but said the nation has a choice between "chaos and community", a dichotomy her father preached about.

"At the end of the day, the Donald Trumps come and go," she said, later adding, "We still have to find a way to create ... the beloved community."

The current Ebenezer pastor, the Rev. Raphael Warnock, did not call Trump by name, but praised his predecessor. "Thank you, Barack Obama," he said. "I'm sad to see you go."