“There is no greater honour than to be given the trust of one’s fellow citizens to lead,” President Higgins says in the letter, “and no greater responsibility than to vindicate that confidence by having their interests, their welfare and their aspirations at the forefront of all that we do.”

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While there is no reference in the letter to the previous administration, it does acknowledge the immense challenges facing the incoming administration – which sees Kamala Harris become both the first woman and the first person of colour to become Vice President of the USA. Both Hope Biden and Kamala Harris were sworn in at what was a moving inauguration ceremony in Washington earlier today.

“As President of the great nation that is the USA,” President Higgins adds, “there is so much positive change that you can bring about over the coming years and so many challenges that we must all face together.”

President Higgins and Joe Biden met on two occasions, when the new President of the USA visited Áras an Úachtaráin as Vice President in June 2016 and again in September 2017.

Meanwhile, Donald Trump has departed The White House earlier this morning. He was flown to Joint Base Andrews, a military facility in Maryland, where a celebration of his great achievements as President had been planned. However, the event turned out to be a damp squib. That didn’t deter Trump from making a typically self-congratulatory speech.

“This has been an incredible four years, we’ve accomplished so much together,” he claimed, going on to thank his family, his friends and his staff. “What we’ve done has been amazing by any standard.”

Among those who chose not to go to the goodbye ceremony were the outgoing Vice President, Mike Pence; the Senate majority leader Mitch McConnell; and the House of Representatives leader of the Republican Party, Kevin McCarthy.

The ex-President finished his speech with a rather bizarre message to the American people: "Have a good life, we will see you soon.”

The reality is that a lot of them would be very happy to see him soon – in jail.