The British Prime Minister has told President Higgins that he is really excited by the things the UK and Ireland are doing together.
In his only public words of the State visit, David Cameron said it is a privilege to be in his job when Anglo-Irish relations are on such an up.
Mr. Cameron greeted Mr. Higgins as he arrived in Downing Street at lunchtime before guiding him up the red carpet and into Number 10, where they briefly posed for photographs before holding bilateral talks followed by a private lunch.
Earlier today the Taoiseach said he would like to see a return visit to Ireland by Queen Elizabeth II in 2016.
The comments from Enda Kenny came after the British Monarch said last night the two countries would stand shoulder to shoulder together in commemorating World War I and the events to mark the creation of the Free State.
Speaking at a business breakfast in London this morning, the Taoiseach described the State visit to Britain by President Michael D. Higgins as momentous.
And he told reporters that a visit to Ireland by the Queen for the 2016 commemorations would be very symbolic.
The President meets Pauline Conway, senior staff nurse, from Co. Wicklow
The President has also been meeting with Irish emigrants who work in the British National Health Service.
He and his wife Sabina toured London's University College Hospital where they met doctors and nurses. They have also met with former members of staff from the wider Irish community as part of the State visit.
Paula O'Brien from Roundstone in Connemara in Co. Galway is the Matron for Surgery at the hospital.
President Higgins and Prof. John Pethica (right), Vice President and Physical Secretary of the Royal Society, with Joseph Roche of the Science Gallery Ireland in London
This morning President Higgins visited the Royal Society of Science in London, where he spoke of the strong influence of Irish people on science in Britain as far back to the 1640s.
He referenced one of his predecessors, Eamon De Valera who was a fellow of the society and also spoke about Robert Boyle the son of the Earl of Cork and one of the most prominent Irishmen to have made science his vocation.
President Higgins has also been attending a youth event hosted by the Mayor of London Boris Johnson in City Hall.
And following a meeting with the Deputy Prime Minister Nick Clegg at Buckingham Palace, the President will address around 700 people at a business and economic focused dinner tonight in the Guildhall.
