He called for a speedy and transparent Israeli inquiry into the incident, which left nine Turkish pro-Palestinian activists dead. However, he stopped short of calling for an international probe.
Soon after the incident Mr Cameron told Parliament that what had happened was “unacceptable” but stressed that he remained a “friend of Israel”.
The Prime Minister used his visit to encourage the European Union to accept a Turkish membership bid, something generally opposed by France and Germany.
The EU has just agreed new sanctions against the Iranian nuclear programme, and Mr Cameron said Turkey was a key ally for them to work.
He said: "We need Turkey's help in making it clear to Iran just how serious we are about engaging fully with the international community.”
Watch Cameron's comments here
