DUP cites Belfast Agreement which it condemned

It is interesting to hear the DUP state that the Brexit backstop contravenes the Belfast (Good Friday) agreement.
Letter to the editorLetter to the editor
Letter to the editor

This from the party that condemned the Good Friday Agreement, and abandoned the unionist people by refusing to participate in the discussions leading up to it.

Surely the DUP should be claiming the backstop contravenes the St Andrews Agreement which they subsequently negotiated with Sinn Féin.

AC Thompson, Dungannon