'No question' of Dublin running North - Thatcher
Margaret Thatcher said there was "no question" of agreeing to give Dublin joint authority over the running of Northern Ireland, official files have revealed.
The late former British prime minister told unionist leaders that the Anglo- Irish Agreement did not threaten British sovereignty.
Her intervention followed a long-running unionist campaign against the 1985 agreement.
The following year, Thatcher wrote: "It is expressly stated in the Agreement that there is no derogation from the sovereignty of the UK government, which remains solely responsible for decisions in relation to the affairs of Northern Ireland."
Thatcher signed the agreement with Taoiseach Garret FitzGerald at Hillsborough.
It prompted widespread unionist protests, including the collapse of the Stormont Assembly and an "Ulster says No" rally at Belfast City Hall.