The prime minister says he will use the Commonwealth summit in Sri Lanka to challenge the Sri Lankan president over allegations of abuses by the country’s security forces.
Flying to the south Asian island nation on the eve of the Commonwealth Heads of Government Meeting, Mr Cameron told reporters: “You can’t make the arguments unless you are there.”
He is due to travel to the north of Sri Lanka to meet journalists and campaigners from the Tamil community who have complained of human rights abuses during and after the bloody end of the 26-year civil war between the Sri Lankan government and Tamil Tiger separatists in 2009.
The meeting is being boycotted by the prime ministers of Canada, India and Mauritius over the claims.
“There is the problem of human rights as we speak today: the people who have disappeared, the lack of free rights for journalists and a free press.
“But I think perhaps most important of all is the need for proper investigations to look into what happened at the end of this very long, appalling civil war.”
He added: “Giving up and staying at home would be bad for the commonwealth and bad for Sri Lanka.
“You can’t make the arguments about the future of the commonwealth unless you are there. You can’t make the arguments about what is happening in Zimbabwe, about the importance of free trade, about how we tackle poverty in our world. Nor can you really shine a spotlight on what is going on in Sri Lanka.”
The Prime Minister has requested a face-to-face meeting with Mr Rajapaksa to discuss his concerns, though it is not yet clear whether this will be granted.
The Sri Lankan leader said: “We are open. We have nothing to hide. If anyone who wants to complain about human rights violations in Sri Lanka, whether it’s torture, whether it is rape, we have a system. If there is any violations, we will take actions against anybody, anybody. I am ready to do that.”
Mr Rajapaksa presented Prince Charles with two cakes to celebrate the royal’s 65th birthday. The anniversary coincides with a trip that sees Charles deputise for the Queen in one of his most important ceremonial duties yet.
Steve Crawshaw from Amnesty International said: “Prince Charles is clearly in a difficult position representing the Queen, who famously avoids politics in all contexts.
“But I very much hope that in private Prince Charles will make absolutely clear how dismayed anybody who cares about human rights would be, seeing what is happening in Sri Lanka today.
“As the representative of the Queen he will no doubt choose his words carefully when speaking publicly, but I hope that even there we will see a reflection and understanding of how serious the problems are that Sri Lanka is facing, and one would hope that will not be swept under the carpet.”