Britain’s Queen Elizabeth will not be attending tomorrow’s Northern Ireland centenary service after being advised by doctors not to travel.

The Foreign Affairs Minister Simon Coveney is due to travel to the event alongside Government Chief Whip Jack Chambers.

That comes after President Michael D Higgins turned down an invitation to the event, warning that it had become politicised and noting it would be inappropriate for the head of State to attend an event that commemorates partition.

The UK Prime Minister Boris Johnson is due to attend; however, Buckingham Palace today confirmed that Queen Elizabeth had “reluctantly accepted medical advice to rest for the next few days.”

"Her Majesty is in good spirits and is disappointed that she will no longer be able to visit Northern Ireland, where she had been due to undertake a series of engagements today and tomorrow,” said a spokesperson.

"The Queen sends her warmest good wishes to the people of Northern Ireland and looks forward to visiting in the future."

The prayer service at St Patrick's Church of Ireland Cathedral in County Armagh is organised by the four main churches in Northern Ireland.

Britain’s Queen Elizabeth accompanies President Michael D Higgins at Windsor Castle, 08-04-2014. Image: Justin Tallis/PA Archive/PA Images

In a statement, the Church Leaders’ Group said it was disappointed she would not be attending.

“We wish to convey to Her Majesty our good wishes and, in doing so, to acknowledge the significance of her commitment to the work of peace and reconciliation, which has meant a great deal to people throughout this island,” it said.

“We hope that tomorrow’s service will provide an opportunity to further that work, with an emphasis on our shared hopes for the future.”

Earlier this month, the Government decided to send Minister Simon Coveney and Junior Minister Jack Chambers to the event in recognition of the church leaders’ “spirit and intentions.”

The Taoiseach later insisted there was “no issue” between the Government and Aras an Uachtarain over the President’s decision to refuse the invitation