SDLP LEADER Mark Durkan has called for a strong and robust bill of rights in Northern Ireland which could mean there was no long-term need for parties in the Stormont Assembly to "designate" whether they are unionist, nationalist or "other".
However, both Sinn Féin and the DUP have said his remarks mean he endorses a key unionist demand for the ending of power-sharing between unionists and nationalists at Stormont.
Mr Durkan last night denied this, claiming that a future without "designation" did not mean an end to coalition and powersharing between unionists and nationalists.
The DUP's Upper Bann MP David Simpson said: "At long last it [the SDLP] accepts that mandatory coalition and designation voting is not the best form of government for Northern Ireland."
Sinn Féin's Deputy First Minister Martin McGuinness accused Mr Durkan of surrendering to unionism over the key issue of a coalition comprising both unionists and nationalists sharing executive power.
"It amazes me how the leader of the SDLP would take up and argue the position of unionists over the past 10 years; that the mandatory coalition should be ended.
"The position he has adopted is effectively throwing his weight behind the likes of Jim Allister and other anti-peace process elements."
Progress on a bill of rights is stalled following the publication of a review last March which exposed key divisions between unionists and nationalists on the issue.
Mr Durkan, addressing the British-Irish Association in Oxford at the weekend, called for that debate to be rejoined.
Speaking on the 10 years since the Belfast Agreement and looking ahead to the next decade, Mr Durkan said the protection of minority interests would be enshrined in a bill of rights while the d'Hondt system would protect political mandates in any future executive.
Details of his speech were later released by his office.
"I remember, at the time, saying that the system of designation was necessary because of what we were coming from but should not be necessary where we were going. I argued that such measures, with their arguably sectarian or sectional undertones, should be biodegradable - dissolving in the future as the environment changed."
He added: "As we move towards a fully-sealed and settled process we should be preparing to think about how and when to remove some of the ugly scaffolding needed during the construction of the new edifice."
Defending these comments last night, Mr Durkan said: "I wrote d'Hondt into the agreement, and it was me who wrote in the stuff about designation as well. You needed it if you were going to go for some form of parallel consent."
He said his critics were accusing him over something he had not said about the future of coalition government at Stormont.
"Mandatory coalition is not a term that is used in the agreement. The agreement is about democratic inclusion and the means provided for that is d'Hondt."
He added: "Mandatory coalition is a DUP term used pejoratively. It's interesting that Mr McGuinness has taken it up, showing Peter Robinson's influence."