DONALD TRUMP WILL become the 45th President of the United States.

He'll be sworn in on the steps of the Capitol Building, to formally take over as Commander-in-Chief.

The businessman says he remains committed to making America "great again".

Formal festivities to mark the transfer of power - the 35th time the Presidency has moved between parties - began yesterday, when the President and vice-President Elect attended Arlington Cemetery to lay wreaths.

Also last night was a concern at the Lincoln Memorial, a short walk from the White House, where Trump said that the forecast of rain for today's ceremonies would not stop it from being "beautiful".

Gavan Reilly reports:

Around 900 thousand people will attend the inauguration in Washington, where there'll be unprecedented levels of security.

Around 100 demonstrations are taking place in Washington today, in support of and against Trump.

While tomorrow, hundreds of thousands of demonstrators are expected for the Women's March on Washington.

Juliette Gash reports;