President Michael D Higgins has written to Joe Biden to congratulate him on assuming office.
Mr Biden and Kamala Harris were inaugurated in Washington this afternoon as the new US President and Vice President.
Mr Biden said that “this is America’s day” and “democracy’s day” as he delivered his first speech as president of the United States.
In the letter, President Higgins told the new US President: “There can be no greater honour than to be given the trust of one's fellow citizens to lead”.
Mr Higgins offered his “most heartfelt congratulations” to his US counterpart, telling Mr Biden “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”.
Mr Higgins said: "There is an Irish saying which you may know: ‘Is ar scáth a chéile a mhaireann na daoine’.
“It means that we live in each other’s shadow and in each other’s shelter. It reminds me that we are all interconnected, we are all interdependent, we all have an effect on each other on this fragile planet that we share.”
"There can be no greater honour than to be given the trust of one's fellow citizens to lead."— President of Ireland (@PresidentIRL) January 20, 2021
President Michael D. Higgins has written to President Joe Biden, offering his "heartfelt congratulations" as @JoeBiden assumes the office of President of the United States. pic.twitter.com/grdf6hBVYN
Mr Higgins stated that the US has been “a true friend to Ireland” and that Mr Biden’s support for the country has been “invaluable”.
The Irish President added that Ireland has made a “valuable contribution” to the US by “providing so many of our daughters and sons.
“The descendants of some turned out the be rather fine Presidents!”
Mr Higgins concluded by saying who he is looking forward to Ireland and the US working closely together in the future and that he hopes to welcome Mr Biden and his wife, Dr Jill Biden, to Ireland when “circumstances permit”.
The President also included a poem - A New Beginning by John O'Donoghue - in his letter to Mr Biden.
Earlier, the Taoiseach congratulated both Mr Biden and Kamala Harris following their inauguration.
Micheál Martin labelled Mr Biden “one of us” as he also paid tribute to Ms Harris on becoming the first woman to hold the office of the US vice president.
“On behalf of the government and people of Ireland, I wish to offer my heartfelt congratulations to President Joe Biden on his inauguration,” said Mr Martin.
“The inauguration of a new US President is a moment of hope and renewal in US political life.
“As he takes the oath-of-office, I know that President Biden will feel the weight of history – the presence of his Irish ancestors who left Mayo and Louth in famine times in search of life and hope.
“He will remember their descendants’ hard struggle as they made their way in and their contribution to the United States. It is the story of Irish-America.
“I hope he will also be conscious of the great pride we in Ireland take in his immense achievement. He is one of us, part of our global family.
“I look forward to welcoming President Biden back to this island and deepening cooperation on global peace, climate change, economic partnership and stability."
He added: “I also wish to pay tribute to Vice President Kamala Harris, who has created history today, and who will help form a diverse and formidable administration.
“I believe Ireland can be a bridge-builder between the United States and the European Union as we all share common values in securing democracy, peace and economic development.
“I am enormously heartened that among his first actions in office will be a re-commitment of the US to the Paris Agreement on climate, and a resetting of the relationship with Europe.
“The challenges of our shared world - and the issues that Joe Biden will face as President – can only be overcome if like-minded leaders come together to tackle them. “
Sinn Féin president Mary Lou McDonald also congratulated the new US president stating he “has long been a friend of Ireland”.
Ms McDonald said: “The connections between our nations are greater than any political alliance - they are bonds of history, family and friendship. The United States has stood with Ireland, including protecting our peace agreements in the Brexit process and President Biden has been a key friend in achieving this.
“I look forward to working with the Biden administration as we continue to realise the transformative potential ofthe Good Friday Agreement in building a new, prosperous and united Ireland.”