Donald Trump has promised he will "make heads spin" and move full-speed ahead with his ambitious agenda after his presidential inauguration on Monday.

Media reports suggest he could announce as many as 100 executive orders within hours of being sworn in as the 47th president.

These presidential directives to federal agencies could affect everything from immigration and border policy to climate action, energy and even cryptocurrency.

While these orders do not require congressional approval, they have the power of law and remain in force until they are cancelled, repealed, halted or expire.

Trump's Republicans have a firm grip on Congress, but advocacy groups and Democratic state governors have vowed to challenge at least some of Trump's plans in the courts and elsewhere.

Here is what to expect.

Here's what to know about Donald Trump's inauguration

Immigration and the border

Deportations

Trump has vowed to "launch the largest deportation program in American history", starting from day one.

Tom Homan, his incoming "border czar", has proposed a hotline for Americans to report undocumented migrants they think have committed crimes. Trump has also said he will end a longtime policy that has kept federal immigration authorities from conducting raids on churches and schools.

Any mass deportation programme is expected to face logistical difficulties and a flurry of legal challenges from immigration and human rights advocates.

Remain in Mexico

Trump may quickly move to re-implement his "Remain in Mexico" policy, which returned about 70,000 asylum seekers to Mexico to await hearings.

End birthright citizenship

Trump has called the 150-year-old constitutional right that says anyone born on US soil is an American citizen "ridiculous" and vowed to scrap it on day one.

But doing that is much more difficult than simply issuing an executive order. Because birthright citizenship is explicitly guaranteed by the US Constitution - getting rid of it would require a legislatively complex change to the foundational American document.

Closing the border on health grounds

A 1944 measure called Title 42 allows the US government to curb migration to protect public health. It was last used during the pandemic, but US media reports that the incoming administration is looking for a disease that would help justify its plans to close the southern US border.

Build the wall

When Trump was first elected president, he signed an executive order to build a border wall. Although parts of the wall have been built, there is still much left uncompleted and he may try to finish what he started.

Trade and economy

Tariffs

Trump has vowed sweeping tariffs on imported goods as part of his promise to prioritise American manufacturing.

Trump introduced tariffs in his first term, including some on China that Joe Biden retained.

But this time he is promising 10% tariffs on all imports, 25% on Canadian and Mexican goods and 60% on things coming from China. He has said he will begin signing executive orders imposing these on day one.

Tariffs are likely to make consumer goods more expensive and could fuel inflation, experts say. Some countries are considering retaliatory tariffs.

Crypto pile

Trump has championed cryptocurrency and his election saw the value of Bitcoin increase by 30%.

Some believe Trump will move quickly to create a federal "Bitcoin stockpile" - a strategic reserve similar to the US's stockpile of gold and oil - that he has said would serve as a "permanent national asset to benefit all Americans". Crypto supporters have heralded this plan as well as expected efforts to reduce oversight of the industry.

Climate and energy

Scrap Joe Biden's climate policies

The outgoing president sees the series of directives, laws and funding programmes he championed to boost green jobs, regulate pollution and fund infrastructure as one of his biggest accomplishments.

Trump has made it clear he hopes to undo much of it. He is expected to use executive orders to remove drilling restrictions on federal land - fulfilling his promise to "drill, baby drill" and increase US energy production and independence. He has also pledged to ban new wind projects and cancel electric vehicle mandates.

Pull out of the Paris Agreement (again)

Within six months of taking office in 2017, Trump withdrew from the Paris climate agreement - a landmark international deal designed to limit rising global temperatures.

Biden moved to rejoin the accord on his first day in office in 2021, but Trump is expected to again withdraw upon his return to the presidency.

Capitol riot

Jan 6 'hostages'

Hundreds of people convicted after the 2021 US Capitol riots are awaiting potential pardons on Monday, when Trump returns to office.

"I am inclined to pardon many of them," he told CNN over the summer. "I can't say for every single one, because a couple of them, probably they got out of control."

Earlier this month, on the fourth anniversary of the riot at the US Congress by Trump's supporters, the Justice Department said that it had arrested 1,583 individuals in relation to the event. More than 600 were charged with assaulting or impeding federal officers.

Foreign policy

Ukraine war

The president-elect had claimed during the campaign that he would end this conflict on day one of his presidency. He has since said that he may need six months. It's unclear what he might do in his first days.

Gaza and Israel

Trump has already taken credit for the ceasefire that will go into effect a day before his inauguration. While Biden called the assertion "a joke", reports suggest that the president-elect and his negotiator's tactics helped secure a deal.

Cuba and Venezuela

Trump could use executive orders to undo Biden's recent decision to remove Cuba from its list of state sponsors of terrorism. He could also reinstate sanctions against Venezuela. Both countries were frequent targets of his ire during his first administration, and that is not expected to change.

Greenland and Canada

Could Trump try to to annex Greenland, an autonomous territory of Denmark and the world's largest island, where the US already has a military base and plenty of troops? Will Canada be the 51st state, as he has repeatedly joked?

Neither plan seems to be realistically on the cards. Still, the president-elect has raised eyebrows in global capitals with his recent taunting of close US allies with the idea of expansionism.

What Trump's win means for Ukraine, Middle East and China

Diversity and gender

DEI

In recent years, schools and businesses across the US have adopted policies designed to support women and racial minorities.

These practices, often classified under "diversity, equity and inclusion" (DEI), have angered many conservatives and faced legal challenges. Trump has promised to dissolve them and major corporations including Meta, Walmart and Amazon have already begun rolling back related initiatives since his election.

Trump could use an executive order to forbid federal funding going to schools or other institutions that have DEI programmes. He could also ban funding for schools that teach "critical race theory" (CRT).

Abortion

Like most Republican presidents before him, Trump is expected to reinstate the "Mexico City policy", which bans federal aid to international groups that provide abortion counselling.

He is also expected to reinstate an abortion rule that prohibits Title X federal health providers, a low-income family planning programme, from mentioning abortion to patients - even if they ask about it. The change effectively stripped tens of millions of dollars from organisations that offer abortion or provide referrals.

Transgender rights

Trump has repeatedly criticised what he calls "transgender lunacy" in schools and healthcare, and has specifically vowed to bar transgender women from competing in women's sports.

TikTok

On Sunday morning, Trump promised on his social media platform, Truth Social, to issue an executive order that would postpone the law banning TikTok from coming into effect.

His order, he said, would give them time to find a US partner to buy a 50% stake in the company.

"I would like the United States to have a 50% ownership position in a joint venture. By doing this, we save TikTok, keep it in good hands and allow it to say up. Without U.S. approval, there is no Tik Tok. With our approval, it is worth hundreds of billions of dollars - maybe trillions," he said in his post.

Trump previously backed a TikTok ban, but recently reversed his stance, pointing to the billions of views he says his videos attracted on the platform during last year's presidential campaign. (BBC)

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