Taoiseach Enda Kenny and British prime minister David Cameron spoke on the phone last night to discuss two official reports confirming the continued existence of the Provisional IRA.

A Government spokesman said the Taoiseach outlined his determination that cross-Border criminality be stamped out. The two men agreed during their 15-minute call that today’s meeting of the Northern Assembly was “very welcome”, he added.

Leading political figures in the Republic have demanded an end to paramilitarism once and for all following the disclosure that the PIRA army council directs the political operations of Sinn Féin.

Minister for Justice Frances Fitzgerald said there was a common assessment in both reports of the reality of the security threat posed by the Provisional IRA.

“It is important for those of us who have been committed all our lives to democratic principles to make one thing clear: the legacy of PIRA is appalling and those with whom they were inextricably linked cannot shirk their responsibilities in relation to it,” said Ms Fitzgerald.

Minister for Foreign Affairs Charlie Flanagan said it was now time for any paramilitary structure associated with the IRA be "severed and dismantled".

In a reference to Sinn Féin, Mr Flanagan said there was a responsibility on all parties associated with paramilitary groups to deal with the issue.

"It is 17 years since the Good Friday agreement. There is no place on the island of Ireland for paramilitary activity or organised criminal activity of a type that we now see."

Fianna Fáil leader Micheál Martin said both reports were succinct, severe and stark.

“The facts within them paint a disconcerting picture and will be a source of major concern for very many people,” he said.

Renua leader Lucinda Creighton said Sinn Féin cannot be "both fish and fowl".

“Either it is a political movement or a puppet of the army council,” she said.