The DUP has strongly rejected Ulster Unionist demands that the U-turn on the Maze peace centre should be followed by another over down-sizing of local councils to 11.
The row threatens to become one of the main themes in the local government election campaign, with a vote for the DUP in next May's elections supporting the changes and a vote for the UUP opposed.
It remains in favour of a reduction to 15 rather than 11, but the DUP's Peter Weir responded: "The boundaries are set by an independent commission and the proposed changes to Belfast bring in four predominantly nationalist wards, but with five predominantly unionist coming in alongside.
"While the UUP appear content with the current 26 councils, we remain committed to reducing the size of government in Northern Ireland and cutting back on unnecessary bureaucracy whether that is at Stormont or in our council chambers," the North Down MLA added.
But former Ulster Unionist leader Tom Elliott hit back: "The fact is that throughout the process of local government reform, the DUP and their Sinn Fein allies refused to accept the concept that electoral areas should reflect local community identities."