David Cameron said he was "committed" to keeping up the pressure on Sri Lanka over his calls for a new "credible, transparent and independent" war crimes investigation by March.
Speaking in Dubai after meeting the Red Arrows at an airshow, the Prime Minister said: "These issues are not solved by one visit, this is not a flash in the pan, it's a dialogue, a conversation, pressure that we need to keep-up over the longer term and I'm committed to doing that."
The Prime Minister's historic visit to northern Sri Lanka highlighted human rights issues at the start of the Commonwealth summit.
A press conference due to be held today with Sri Lankan President Mahina Rajapaksa was cancelled at the last minute.
Democratic freedoms are being clipped and police vans are waiting for those who might disagree what the Sri Lankan government is doing.