Lebanon's prime minister Fouad Siniora yesterday asked the United Nations Security Council to create a special tribunal to try suspected killers of Rafiq Hariri, the former leader, a move that could heighten the confrontation between the government and the opposition.

In a letter to Ban Ki-Moon, the UN secretary general, Mr Siniora requested that the UN set up an international court because all attempts to ratify it within Lebanon had been exhausted, with the opposition preventing the convening of a parliamentary session.