US President Donald Trump has touted his “unrelenting action” since retaking the White House in his first speech to the US Congress.

Trump wasted no time in touting his electoral victory during his speech on Tuesday night (local time), claiming his win gave him “a mandate like has not been seen in many decades”.

“Six weeks ago, I stood beneath the dome of this Capitol and proclaimed the dawn of the Golden Age of America. From that moment on, it has been nothing but swift and unrelenting action to usher in the greatest and most successful era in the history of our country,” he said.

“We have accomplished more in 43 days than most administrations accomplished in four years or eight years. And we are just getting started.”

In response, Republicans in the chamber stood up and cheered, chanting, “USA!”

However, as Trump started speaking again, some of those assembled booed him.

Minutes into his speech, Democrat Al Green was escorted out of the chamber after lifting his cane to point at Trump and yelling that he had no mandate.

“Members are engaging in wilful and continuing breach of decorum, and the chair is prepared to direct the Sergeant at Arms to restore order to the joint session,” House Speaker Mike Johnson said.

“Mr Green take your seat. Take your seat, sir.”

As Green was escorted out, some Republicans sang out, “Na-na-na-na, hey, hey, hey, goodbye.”

Democrats hold up protest signs while Trump speaks. Photo: AAP

After Green’s departure, Trump said: “I look at the Democrats in front of me, and I realise there is absolutely nothing I can say to make them happy or to make them stand or smile or applaud.”

Democrats also held up signs that read “false”, “Musk steals”, “save Medicaid”, and “protect veterans” throughout Trump’s speech, while others wore T-shirts with slogans and one group protested in pink.

Democrats also pointed to tech billionaire Elon Musk, who was sitting in the gallery, when Trump said “the days of rule by unelected bureaucrats are over”.

The partisan rancour was reflective of the tumult that has accompanied his first six weeks in office, as he has upended US foreign policy, ignited a trade war with close allies and slashed the federal workforce since he took office six weeks ago.

“To my fellow citizens, America is back,” Trump began to a standing ovation from fellow Republicans.

“Our country is on the verge of a comeback the likes of which the world has never witnessed, and perhaps will never witness again.”

The primetime speech capped a second day of market turmoil after Trump imposed sweeping new tariffs against Mexico, Canada and China.

“Whatever they tariff us, we tariff them. Whatever they tax us, we tax them,” he said on Tuesday.

“If they do non-monetary tariffs to keep us out of their market, then we do non-monetary barriers to keep them out of our market.”

He spoke in the House of Representatives, where lawmakers huddled in fear for their lives a little over four years ago while a mob of Trump supporters ransacked the Capitol in an unsuccessful effort to overturn Democrat Joe Biden’s 2020 victory.

World leaders were watching Trump’s speech closely, a day after he paused all military aid to Ukraine.

The suspension followed an Oval Office blowup in which Trump angrily upbraided Ukrainian President Volodymyr Zelensky in front of TV cameras.

The pause in aid threatened Kyiv’s efforts to defend against Russia, which launched a full-scale invasion three years ago, and further rattled European leaders worried that Trump is moving the US too far toward Moscow.

Later in his speech, Trump said Zelensky had written to him to say Ukraine was ready to “come to the negotiating table as soon as possible to bring lasting peace closer”.

“My team and I stand ready to work under President Trump’s strong leadership to get a peace that lasts,” he said Zelensky had written in his “important letter”.

The quotes appeared to match a social media post by Zelensky. It is unclear if he has also written to Trump.

While Trump has appeared to fault Ukraine for starting the war, a new Reuters/Ipsos poll found 70 per cent of Americans – including two-thirds of Republicans – say Russia was more to blame.

Trump’s 25 per cent tariffs on Mexico and Canada, two of the country’s closest allies, and an additional 10 per cent on Chinese imports deepened investor concerns about the economy. The Nasdaq Composite is down more than 9 per cent from its record closing high on December 16.

Just one in three Americans approve of Trump’s handling of the cost of living, according to the Reuters/Ipsos poll, a potential danger sign amid worries his tariffs could increase inflation.

Earlier, a senior White House official said the theme of Trump’s speech was the “renewal of the American dream”. The speech is akin to a State of the Union address but not called that in a president’s inaugural year.

-with AAP