Trump; Republican candidate sworn in as 45th US president (Photo)

Donald Trump was sworn in Friday as the 45th president of the United States, taking the oath of office at the US Capitol as hundreds of thousands of ecstatic supporters cheered the historic handover of power.

The 70-year-old Republican placed his hand on two Bibles -- his own and one used by Abraham Lincoln -- to take the solemn oath, ushering in a new political era that has been met with delight and dread in equal measure.

"I, Donald John Trump, do solemnly swear that I will faithfully execute the office of president of the United States, and will to the best of my ability, preserve, protect and defend the Constitution of the United States. So help me God," he declared, before pumping his fist in the air several times.