Donald Trump has told thousands of roaring supporters he will usher in a new era of American prosperity as he takes a victory lap inside a packed Washington arena, a day before he returns to power with plans to aggressively reshape US immigration and trade policy.
"Tomorrow, at noon, the curtain closes on four long years of American decline, and we begin a brand new day of American strength, prosperity, dignity and pride," he said on Sunday.
Trump's 'Make America Great Again Victory Rally' took place at Capital One Arena, an indoor hockey and basketball venue that will also host some of Monday's inauguration festivities after forecasts of bitter cold prompted officials to move the planned outdoor events inside.
Donald Trump says he will "fix every single crisis" facing America. (AP PHOTO)
The rally resembled the free-wheeling campaign speeches that have been a Trump staple since his first White House run in 2016. The event marked his first major address in Washington since he delivered a speech on January 6, 2021, to his supporters that preceded the storming of the US Capitol.
"This is the greatest political movement in American history, and 75 days ago, we achieved the most epic political victory our country has ever seen," he said.
"Starting tomorrow, I will act with historic speed of strength and fix every single crisis facing our country."
Trump said he would shut down the southern border, "bring back law and order to our cities" and "get radical woke ideologies the hell out of our military", among other promises.
"By the time the sun sets tomorrow, the invasion of our country will have come to a halt," he said.
Donald Trump says immigration will be a target of his first executive actions after taking office. (AP PHOTO)
Ahead of the event, Trump's fans, many dressed in the campaign's trademark red jackets and MAGA hats, waited in a cold, driving rain along several downtown Washington blocks, some chanting "USA! USA!"
Large swathes of the streets around the US Capitol and White House have been blocked off by steel fences since last week, and police were visible throughout the city.
Trump's rally, along with his inaugural address on Monday, could preview the tone he plans to adopt during his second White House term.
In recent weeks, Trump has bewildered foreign allies by musing aloud about taking over Greenland and the Panama Canal and turning Canada into a US state.
Security in Washington is tight ahead of the presidential inauguration. (AP PHOTO)
Immigration will be a target of Trump's first executive actions after taking office, along with energy issues and policies aimed at promoting diversity, equity and inclusion, his incoming national security adviser Mike Waltz told CBS.
"The American people gave him a clear mandate. Lock down our border, deport the worst of the worst, take on the cartels," Waltz said in an interview with Face the Nation.
Stephen Miller, a top Trump adviser, told the audience that Trump would issue an executive order on Monday "ending the border invasion, sending the illegals home and taking America back," drawing cheers.
In recent weeks, Trump has bewildered foreign allies by musing aloud about taking over Greenland and the Panama Canal and turning Canada into a US state.
Trump had breakfast with Republican US senators at Blair House, the guest quarters across from the White House, on Sunday before later visiting Arlington National Cemetery to place a wreath at the Tomb of the Unknown Soldier.
Donald Trump supporters have arrived in Washington en masse for the inauguration. (AP PHOTO)
The world's richest man, Elon Musk, who has become a Trump confidant since spending more than $US250 million ($A404 million) on his campaign, is scheduled to speak at the event, along with Vice President-elect JD Vance, Ultimate Fighting Championship CEO Dana White, conservative activist Charlie Kirk and conservative commentator Megyn Kelly.
TikTok CEO Shou Zi Chew planned to attend the rally, hours after the company announced it was restoring its service thanks to Trump's promise to delay a US ban that took effect on Sunday. Chew is also expected to join other tech executives at Trump's inauguration on Monday.
Biden, meanwhile, made his last official trip as president on Sunday to Charleston, South Carolina, to mark Martin Luther King Jr Day, which is also on Monday. He attended services and spoke about King's legacy at Royal Missionary Baptist Church, while also urging despondent fellow Democrats not to give up hope.
The inauguration is scheduled for noon on Monday (4am AEDT Tuesday), when Trump will take the presidential oath of office inside the rotunda of the Capitol building, after the cold weather prompted organisers to move the ceremony indoors.
Approximately 25,000 law enforcement personnel will be on hand to provide security.