Former Lib Dem leader and peace envoy Paddy Ashdown said neither Israel nor Hamas "can blast their way to victory" and called for both sides to engage in peace talks.
Lord Ashdown told BBC Radio 4's Today programme: "There is only one way to get peace now, and that is for the sides to sit down and start talking to each other.
"Hamas has to be at the table. Who's firing the rockets? It's Hamas, and so you have to talk to them.
"If an individual or an organisation has the support of the people who it represents, in the end you have to talk to them. We had to talk to the IRA, for goodness' sake."
There have been two days of quiet in Gaza. No rockets or missiles, no more destroyed houses, no more ambulance sirens screaming.
A three-year-old girl has been rescued from Gaza and brought to London for life-saving heart surgery.
A small team of NHS doctors and surgeons is travel to Gaza to set up facilities and establish how best to use specialists and equipment.