Leaders from around the world reacted to Donald Trump's return Monday to the White House, offering congratulations and urging good relations with the mercurial leader.

President Donald Trump announced severe new restrictions on immigration and asylum in the United States hours after taking office Monday, declaring that he will send troops to the U.S.-Mexico border and attempt to end birthright citizenship.

Trump declared a national emergency at the southern border and used a careening press conference in the Oval Office to announce the controversial order seeking to revoke the right of U.S. nationality to anyone born in America.

U.S. President Donald Trump on Monday promptly reversed Joe Biden's decision to remove Cuba from a blacklist of state sponsors of terrorism, announced days earlier as part of a deal to free prisoners.

Donald Trump cast himself both as a peacemaker and fierce defender of U.S. interests in a mercurial return to the White House on Monday, vowing to seize the Panama Canal but also imploring Russia to make a deal on Ukraine.

Billionaire tech mogul Elon Musk said Tuesday his critics needed "better dirty tricks" after a row erupted over a gesture he made at an inauguration event for U.S. President Donald Trump that some likened to a Nazi salute.

Donald Trump was sworn in for a historic second term as president on Monday, pledging a blitz of immediate orders on immigration and the U.S. culture wars as he caps his extraordinary comeback.

France and Europe risk being dominated, crushed and marginalized if they do nothing to counter the policies of Donald Trump, the French prime minister said Monday before his inauguration as US president.

"The United States, with the inauguration of the president, has decided on a politics that is incredibly dominating... If we do nothing then our fate will be simple. We will be dominated, we will be crushed, we will be marginalized. It is up to us, French and Europeans," Prime Minister Francois Bayrou said in the southwestern city of Pau.

Donald Trump, who overcame impeachments, criminal indictments and a pair of assassination attempts to win another term in the White House, will be sworn in as the 47th president on Monday, taking charge as Republicans assume unified control of Washington and set out to reshape the country's institutions.

Trump is expected to act swiftly after the ceremony, with executive orders already prepared for his signature to jumpstart deportations, increase fossil fuel development and reduce civil service protections for government workers, promising that his term will bring about "a brand new day of American strength and prosperity, dignity and pride."

Poland's six-month presidency of the European Union is firmly focused on security. As Europe's biggest land war in decades rages, fewer places highlight the challenges and contradictions of defending the bloc and its values more starkly than the border with Belarus.

Some 13,000 border guards and soldiers protect around 400 kilometers of border. It's become a buffer zone since Belarus' ally, Russia, invaded neighboring Ukraine three years ago. Similar fortifications farther north line Poland's frontier with the Russian region of Kaliningrad.

Pope Francis said Donald Trump's plans to impose mass deportations of immigrants would be a "disgrace," as he weighed in on the incoming U.S. president's pledges nearly a decade after calling him "not Christian" for wanting to build a wall along the U.S.-Mexican border.

History's first Latin American pope was asked about the Trump administration pledges of deportations during an appearance Sunday night on a popular Italian talk show, Che Tempo Che Fa.