Tamils now living in London demonstrated noisily outside the Commonwealth Secretariat on Friday (November 15) to coincide with the opening ceremony of the Commonwealth Heads of Government Meeting (CHOGM) in Sri Lanka.
They are angry that British Prime Minister David Cameron chose to attend the summit, saying he should have followed the leaders of Canada and Mauritius and boycotted the Colombo talks over alleged abuses. India's prime minister is also not attending, but that is in part due to domestic pressures.
The meeting of around 50 mostly former British colonies has brought intense scrutiny of Sri Lanka's human rights record four years after the civil war ended.
The London protest of around 150 people called for Sri Lanka to be suspended from the Commonwealth, as Nigeria, Pakistan, Zimbabwe and Fiji have been in the past.
"We see a selective approach from the Commonwealth side on Sri Lanka, they are not punishing Sri Lanka as they did with other countries. So we are strongly calling for that suspension, that should happen today," said Raj Vakisan, Advocacy Co-ordinator for the British Tamils Forum.
Sri Lankan President Mahinda Rajapaksa had hoped the November 15-17 meeting would prove an advertisement for progress and economic growth for the country.
Instead, the summit has been overshadowed by allegations of state-sponsored rape and torture.
Among the protesters in London were many Tamils who witnessed the 2009 attacks by government forces.
The United Nations wants an international inquiry into allegations of war crimes in the final months of the conflict, something the Sri Lankan government has resisted.
Rajapaksa has rejected criticism saying this week his country had "nothing to hide".
Presented by Adam Justice