[WASHINGTON] President Donald Trump urged Americans to abandon conflict and help him remake the fabric of the country in his first address to Congress, a moment he hopes will turn the page on his administration's chaotic beginning and bring clarity to his policy agenda.

"What we are witnessing today is the renewal of the American spirit," Mr Trump said.

"Our allies will find that America is once again ready to lead. All the nations of the world - friend or foe - will find that America is strong, America is proud, and America is free."

Mr Trump arrived at the lectern in the House of Representatives with a heavy burden: to explain his plans to skeptics, including a growing number of fellow Republicans.

His address comes six weeks into a term marked by record highs in the US stock market but also mass protests against his presidency, court battles over a proposed travel ban, and a controversial habit of policy making via Twitter.

Mr Trump faced a choice in his speech to either echo his inaugural address and stoke his nationalist and conservative base, or to reach toward the political centre and explore compromise with his opponents.

"I am here tonight to deliver a message of unity and strength," Mr Trump said, according to prepared remarks released by the White House.

"From now on, America will be empowered by our aspirations, not burdened by our fears."

Lawmakers, investors and voters expected Mr Trump's speech to provide some details on his plans to repeal and replace Obamacare, pay for a 10 per cent increase in defence spending without cutting Social Security and Medicare and overhaul the US tax code.

US stocks have led a global rally in riskier assets since Mr Trump's election, though gains have also come amid strengthening fundamentals from corporate profits to economic data.

Almost US$3 trillion has been added to the value of US stocks since Nov 8, as the S&P 500 Index has surged 11 per cent to a record and the Dow Jones Industrial Average just capped a 12th day of closing at an all-time high, matching its longest-ever streak set in 1987.

Mr Trump said that since his election Ford Motor Co, Fiat Chrysler Automobiles NV, General Motors Co, Sprint Corp, Softbank Group Corp, Lockheed Martin Corp, Intel Corp, Wal-Mart Stores Inc "and many others" had announced billions of dollars in investments and "tens of thousands of new American jobs."

"The stock market has gained almost three trillion dollars in value since the election on Nov 8th, a record," he said.

Foreign currency markets have lost some of their enthusiasm for the Trump trade, with the US dollar lower by more than 3 per cent since Jan 3 after surging 6.5 per cent following the election, according to the Bloomberg Dollar Spot Index.

Hours before his speech, Mr Trump signalled to network television anchors in a private meeting at the White House that he's open to legislation that would overhaul the nation's immigration laws. That set off speculation the president might be poised to make an about-face and support a path to citizenship for undocumented immigrants. A senior administration official said the president has not changed his core positions on the issue.

"By finally enforcing our immigration laws, we will raise wages, help the unemployed, save billions of dollars, and make our communities safer for everyone," Mr Trump said in the prepared remarks.

Optimism, Unity

The president made a stab at encouraging optimism and unity, ideals at odds with much of his governance. Many of his first acts have proved divisive, especially executive orders to enhance immigration enforcement and ban US entry to travellers from seven predominantly Muslim nations, as well as a decision to revoke an Obama-era directive intended to protect transgender children from bullying at schools.

"The time for small thinking is over," Mr Trump said in the prepared remarks.

"The time for trivial fights is behind us. We just need the courage to share the dreams that fill our hearts. The bravery to express the hopes that stir our souls. And the confidence to turn those hopes and dreams to action."

In a signal of where Mr Trump stands on immigration, among the guests invited to sit with First Lady Melania Trump were Jessica Davis and Susan Oliver, widows of California law enforcement officers killed in the line of duty by an undocumented immigrant, and Jamiel Shaw Sr, whose son was shot by a gang member in the country illegally, according to the White House.

Maureen McCarthy Scalia, the widow of the late Supreme Court Justice Antonin Scalia, also was invited ahead of Senate hearings next month on Mr Trump's nominee to fill the Scalia vacancy, federal appeals court judge Neil Gorsuch.

Democratic women in the House chamber wore white in a show of protest and solidarity. Several Democrats invited undocumented immigrants as their guests. Supreme Court Justice Ruth Bader Ginsburg, who called Mr Trump a "faker" during his campaign, planned to skip the address.

The Trump Cabinet member who didn't attend the speech in the event of catastrophe - the so-called designated survivor - was Veterans Affairs Secretary David Shulkin.

'Massive Tax Relief'

Congressional Republicans were looking for any endorsement by Mr Trump of a border-adjusted tax, a roughly US$1 trillion revenue-raiser that sits at the heart of House Speaker Paul Ryan's plan to slash corporate and individual tax rates. The plan is struggling for support, and proponents are eager for a boost from Mr Trump, who has so far sent mixed signals on the proposal.

"My economic team is developing historic tax reform that will reduce the tax rate on our companies so they can compete and thrive anywhere and with anyone," Mr Trump said in the prepared remarks, which didn't specifically mention the border-adjusted tax.

"At the same time, we will provide massive tax relief for the middle class."

Under the border-adjustment plan, the current corporate income tax would be replaced with a 20 per cent levy on imports and domestic sales, while exempting exports. The measure has stirred sharp divisions among businesses: Retailers, automakers and oil refiners that rely on imported goods and materials oppose it, while export-heavy manufacturers support it.

Critics argue that the plan would raise prices for consumers, while proponents say that, in theory, international currency-exchange rates will adjust to prevent raising consumer prices or favouring exporters.

Replacing Obamacare

Mr Trump implored Congress to repeal and replace the Affordable Care Act, a centrepiece of his campaign.

"Mandating every American to buy government-approved health insurance was never the right solution for America," he said in prepared remarks.

"The way to make health insurance available to everyone is to lower the cost of health insurance, and that is what we will do."

But the effort has stalled, with Republicans divided on a policy to replace the law known as Obamacare and facing protests from voters in their home districts.

Mr Trump described the law as "collapsing" and said that "action is not a choice".

"Democrats and Republicans," Mr Trump said, should "work with us to save Americans from this imploding Obamacare disaster."

Mr Trump has previously proposed spending as much as US$1 trillion on US roads, bridges, sea ports, airports and other public works, and his advisers have suggested that the programme would rely on private-sector funding. The president renewed the commitment but provided no new details in Tuesday's address.

"To launch our national rebuilding, I will be asking the Congress to approve legislation that produces a US$1 trillion investment in the infrastructure of the United States - financed through both public and private capital - creating millions of new jobs," he said in the prepared remarks.

BLOOMBERG