Martin McGuinness has announced he is stepping down from frontline politics because of ill health.

The 66-year-old, who has been unwell for a number of weeks, said he will not stand for election to the Northern Ireland Assembly in March.

Mr McGuinness resigned as Deputy First Minister last week following a row between his party Sinn Féin and the Democratic Unionist Party over a botched green energy scheme. He also cited his illness as a factor in that decision.

Details of his condition have not been disclosed by the party. However, Irish broadcaster RTÉ has reported he is suffering from a rare heart condition.

"The question I asked myself was 'are you physically capable of fighting an intensive 5/6 week election and doing it to my full abilities?' I rapidly came to the conclusion that I am not in any physical state to fight such a campaign. So I have taken the decision that I will not be a candidate in the upcoming election," he said.

He added a new candidate to lead the party into the elections will be announced next week and that while his electoral career has come to an end, his political career has not.

"I hopefully will overcome this illness through time." he said. "I am very determined to be an ambassador for peace, unity and reconciliation.

"Reconciliation, I have always believed, is the next vital stage of the peace process.

He added: "My record of reaching out, whether it be to Queen Elizabeth – and her record of reaching out to me on several occasions – my visits to the Somme, to Flanders field, have not been reciprocated by the DUP and that is a particular disappointment to me."

Northern Ireland will hold elections on 2 March to choose a new Assembly following the collapse of the Stormont power-sharing executive, triggered by the Sinn Féin Deputy First Minister's resignation.

The fallout between his party and Democratic Unionist Party was over the Renewable Heat Incentive (RHI), an initiative designed to encourage businesses to use green energy. However subsidies were found to be overly generous and ineffective, with projections estimating an overspend of £490m.