President Joe Biden and president-elect Donald Trump are meeting in the Oval Office, resuming a tradition that Trump himself flouted in 2020.

The two men, sitting near a crackling fire, shook hands. Biden spoke first, calling for a “smooth transition” and telling Trump he would do “everything we can to make sure you’re happy.”

Trump then thanked Biden.

“Politics is tough, and in many cases the world isn’t very beautiful, but it’s a beautiful world today,” Trump said. “And I really appreciate it. Such a smooth transition, it’ll be as smooth as possible, and I really appreciate that, Joe.”

They did not answer questions.

First lady Jill Biden joined President Biden in greeting Trump upon his arrival, according to the White House. She handed Trump a handwritten letter of congratulations for Melania Trump, which also expressed her team’s willingness to help with the transition.

The first lady’s office confirmed that a joint invitation had been extended to the Trumps to meet at the White House. But Melania Trump did not go to Washington with her husband on Wednesday.

“Her husband’s return to the Oval Office to begin the transition process is encouraging and she wishes him every success,” Melania Trump’s office said in a statement.

In 2016, Michelle Obama welcomed Melania Trump to the White House when then-President Barack Obama invited Trump just days after the election. The two men met for 90 minutes and Obama called the conversation “excellent.”

After losing the 2020 election, Trump broke with two traditions that demonstrate the peaceful transfer of power in American democracy.

First, he refused to invite Biden, then president-elect, to the White House in the weeks after the race, while maintaining that he had not lost. He later skipped Biden’s inauguration, leaving Washington just hours before the ceremony began.

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But those customs returned when Trump arrived at the White House on Wednesday.

This is Trump’s first return to the White House since he ended his presidency amid election denialism four years ago. A week before he left office, he was impeached by the House for the second time as lawmakers charged him with “incitement of insurrection” after his supporters violently stormed the U.S. Capitol on January 6 2021.

Trump vowed to return and his comeback was completed last week. He swept all seven swing states, winning 312 electoral votes to Vice President Kamala Harris’ 226 votes, and is on track to win the popular vote.

Biden spoke with Trump on November 6 to congratulate him and extend a political olive branch with an invitation to the White House.

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White House press secretary Karine Jean-Pierre said Tuesday that Biden did so because “he believes in norms.”

“It’s important not only because it’s important to him, but also because it’s important to the American people,” Jean-Pierre said. “The American people deserve this. They deserve a peaceful transfer of power. They deserve a smooth transition. And that’s what you’re going to see.”

Vice President Harris did not attend Wednesday’s meeting.

Last month, before Election Day, the White House said Biden would attend the inauguration regardless of who wins.

Biden made preserving democracy a key message of his 2020 campaign and his 2024 re-election efforts before dropping out, repeatedly calling Trump a threat to the institution on January 6.

“He wants to show the American people that the system works,” Jean-Pierre said.

Asked by ABC News White House correspondent Karen Travers about the agenda for their meeting, Jean-Pierre said the conversation would be private but reporters would be allowed into the room to capture the beginning of their session.

National Security Advisor Jake Sullivan, however, said last weekend that Biden and Trump would address both domestic and foreign policy issues.

In Washington, Trump also stopped near the Capitol to meet with House Republicans.

Republican leaders in the House of Representatives scored a first victory Tuesday as the party moves closer to a “trifecta” – control of the White House, Senate and House. ABC News has not yet projected the balance of power in the House, even though Republicans are three seats short of the majority.

“It’s a new day in America,” President Mike Johnson proclaimed. He said Republicans were ready to start implementing Trump’s agenda on day one of his administration.

ABC News’ Justin Gomez and Kelsey Walsh contributed to this report.