A call by a former senior aide to Tony Blair for the UK to start talks with al-Qaeda has been dismissed as "inconceivable" by the government.
Jonathan Powell was a key member of Tony Blair's government
Jonathan Powell, an ex Downing Street chief of staff, told the Guardian the Northern Ireland peace deal showed talking to terror groups could work.
He also said he would talk to Hamas in Gaza if he still worked at Number 10.
The Foreign Office said the government would not talk to any group actively promoting its aims through violence.
Mr Powell was one of the key negotiators for the government in reaching a settlement in Northern Ireland during Mr Blair's time at Number 10.
BBC political correspondent James Hardy said Mr Powell now believes that deal would not have been possible without secret channels being opened to the IRA three decades earlier.
In an interview with the Guardian, Mr Powell said talks with al-Qaeda might seem pointless at present, but ultimately a political solution would need to be developed alongside a security response.
He said: "There's nothing to say to al-Qaeda and they've got nothing to say to us at the moment, but at some stage you're going to have to come to a political solution as well as a security solution.
"And that means you need the ability to talk.
"If I was in government now I would want to have been talking to Hamas, I would be wanting to communicate with the Taleban and I would want to find a channel to al-Qaeda."
But Mr Powell's suggestion was dismissed by the Foreign Office.
A spokesman told The Guardian: "It is inconceivable that Her Majesty's government would ever seek to reach a mutually acceptable accommodation with a terrorist organisation like al-Qaeda."