Donald Trump has been sworn in as the 47th President of the United States, completing perhaps the most remarkable political comeback in American history.
The Republican, the first convicted felon ever to become commander-in-chief, signed a series of executive orders at his inauguration parade and later at the Oval Office on issues ranging from climate change, immigration and the January 6 riots - with some bound to cause controversy.
Proclaiming that a "golden age begins right now", Mr Trump also said he would rename the Gulf of Mexico the "Gulf of America" and take back the Panama Canal in his inauguration address.
"I'm going to put America first... The scales of justice will be rebalanced," he said. "From this moment on, America's decline is over."
Follow live: Trump returns to power
In his executive orders, he "declared a national emergency" at the southern border with Mexico as well as a "national energy emergency".
He granted pardons and commuted sentences for people related to the January 6 riots and targeted automatic citizenship for US-born children of illegal immigrants;
He also took the US out of the Paris climate agreement and the World Health Organisation, as well as promising tariffs and taxes on foreign countries to enrich American citizens.
During his inauguration speech, he pledged to "build the strongest military the world has ever seen" and also turned his attention to the Panama Canal.
"China is operating the Panama Canal, and we didn't give it to China. We gave it to Panama, and we're taking it back."
The president did not say exactly what measures he would take to retake control of the crucial waterway.
Panama's President Jose Raul Mulino responded shortly after, saying the canal "is and will continue to be Panamanian".
Mr Trump has also spent recent weeks talking about taking control of Greenland and making Canada a US state, but these claims did not feature in his inaugural address.
He did, however, include his promise to rename the Gulf of Mexico the "Gulf of America".
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'Saved by God to make America great again'
Speaking about his journey back from defeat in 2020, Mr Trump said "the journey to reclaim our republic has not been an easy one".
He touched on the assassination attempt in which he was shot: "I was saved by God to make America great again."
"It is my hope that our recent presidential election will be remembered as the greatest and most consequential election in the history of our country.
"As our victory showed, the entire nation is rapidly unifying behind our agenda with dramatic increases in support from virtually every element of our society," he said.
Starmer and Meloni among world leaders congratulating Trump
A host of world leaders issued their congratulations and well-wishes to President Trump.
Sir Keir Starmer referenced the centuries-old relationship between the US and the UK, adding: "Together, we have defended the world from tyranny and worked towards our mutual security and prosperity.
"With President Trump's longstanding affection and historical ties to the United Kingdom, I know that depth of friendship will continue."
Israeli Prime Minister Benjamin Netanyahu said: "I look forward to working with you to return the remaining hostages, to destroy Hamas' military capabilities and end its political rule in Gaza, and to ensure that Gaza never again poses a threat to Israel."
Giorgia Meloni, prime minister of Italy, said she was "certain that the friendship between our nations and the values that unite us will continue to strengthen the cooperation between Italy and the USA".
Meanwhile, King Charles wished the new president well, sending a personal message to Mr Trump congratulating him and reflecting on the enduring special relationship between the UK and US.
What happened with the kiss?
Moments before he began his address, his wife Melania stood beside him as he gave the oath of office for the second time in his life.
A gun salute marked the beginning of the 47th US president's administration.
A host of former presidents and foreign politicians were in the room to watch the transfer of power - as well as a number of tech titans and billionaires who have sought to curry favour with Mr Trump.
But the ceremony was not without an awkward moment, with Mr Trump going to kiss his wife but missing her face as he went to take his seat in the Capitol Rotunda before he was sworn in.
The ceremony is usually held outside but was brought inside the Capitol Rotunda because of the weather - it was expected to be the coldest inauguration day in 40 years.
Earlier in the day, Mr Trump and his wife Melania joined Joe Biden and his wife Jill for the tea, which is traditionally held on inauguration day to welcome the new president. Afterwards, they all travelled in the same car in a motorcade to the Capitol.
(c) Sky News 2025: Donald Trump sworn in as US president for second time, telling Americans: 'The golden age begins right now'