Trump’s remarks followed a series of angry posts on his Truth Social app, calling her “DELUSIONAL”.

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Trump wins New Hampshire primary, beating rival Nikki Haley who vows to stay in the race

Trump wins New Hampshire primary, beating rival Nikki Haley who vows to stay in the race

Trump’s address was loaded with his trademark ominous warnings about immigration as he continued to lie about winning the 2020 election.

In her own speech, Haley insisted that the race was “far from over” and told supporters that Democrats actually want to run against her former boss, due to his record of sowing “chaos”.

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“They know Trump is the only Republican in the country who Joe Biden can defeat,” Haley, 52, said.

Despite now adding New Hampshire to his previous easy victory in Iowa – and looking near unstoppable to become the Republican candidate in November – Trump kept to his hard-right messaging, with no hint of reaching out to the more moderate voters who supported Haley.

At one point swearing on prime time TV, Trump said the United States was a “failing country” and claimed that undocumented migrants were coming from psychiatric hospitals and prisons, and “killing our country”.

Biden, meanwhile, won an unofficial Democratic primary in New Hampshire, giving him a symbolic boost.

Biden said “it is now clear that Donald Trump will be the Republican nominee”.

“And my message to the country is the stakes could not be higher. Our Democracy. Our personal freedoms – from the right to choose to the right to vote,” Biden said in a statement.

With strong turnout in the northeastern state, Haley had hoped for a major upset. But US broadcasters quickly projected her defeat as the first tallies came in.

Trump was already the runaway leader in national Republican polling, despite two impeachments as president, and four criminal trials hanging over him since leaving office.

While Haley repeatedly questioned Trump’s mental fitness, her efforts in New Hampshire were not expected to create much more than a speed bump for the populist right-winger’s surge to November.

New Hampshire was markedly more Haley-friendly than the states she will subsequently face, should she stay in the race, and continuing into February and South Carolina will be a tough sell.

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Haley’s campaign said on Tuesday it intends to keep her candidacy alive through “Super Tuesday” in early March, when 16 states vote.

Trump won a crushing victory in the first Republican contest in Iowa last week, with Haley a distant third.

What was once a crowded field of 14 candidates then narrowed to a one-on-one match-up on Sunday after Florida Governor Ron DeSantis dropped out, following his second-place Iowa finish.

No Republican has ever won both opening contests and not ultimately secured the party’s nomination.

The Republican race pits hawkish Haley against Trump, who had cordial and friendly engagements with the leaders of China, Russia and North Korea when he was president.

On China, the two Republican candidates have so far struck different tones.

Trump has said little about China in recent months, while Haley has made it a consistent pillar of her foreign policy during her presidential campaign.

In a CNN town hall last week, Haley called China the “number one national security threat” to the United States and criticised Trump for not being tough enough on Beijing.

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The former US ambassador to the United Nations has also pushed out messaging on stopping Beijing’s role in fentanyl trafficking, countering the country’s theft of US intellectual property, and strengthening deterrence in light of Beijing’s potential aggression against Taiwan.

She has vowed to bring a “sea change” in US policy towards China, and has repeatedly said she would push Congress to revoke China’s preferential trade status until the flow of fentanyl into the US stops.

Unlike Haley, Trump has a record of dealing with China at the presidential level. But while he is known for launching a trade war with China, he has also embraced a transactional approach that could foster new deals.

In 2020, after imposing four rounds of tariffs on imported goods from China, Trump signed a trade deal with China that committed Beijing to purchase US$200 billion of additional US exports before December 31, 2021.

More recently, Trump has floated the idea of a 10 per cent tariff on foreign imports and to phase out all imports of “essential goods” from China in four years.

Meanwhile, the former president has not provided a firm answer on whether he would defend Taiwan in the event of a conflict with Beijing, arguing that doing so would put him in a “very bad negotiating position” if he became president.

Haley, on the other hand, has said “we will do whatever we need to do to defend Taiwan”, though she has also said that “we don’t need to put troops on the ground anywhere”.

The former president has also praised Chinese President Xi Jinping, and has been criticised for inconsistent support of US allies in light of China’s growing influence.

“I love China. I love everybody but they can’t take advantage of us,” Trump said after winning the Republican contest in Iowa earlier this month. “If I get in [China knows] it’s not going to be so good for them.”

Additional reporting by Reuters