David Cameron threatens to push for an independent international inquiry into allegations of war crimes at the end of Sri Lanka’s civil war if the island nation does not conduct its own probe by 2014.
Mr Cameron has been the most vocal critic of Sri Lanka’s record on rights during a biannual summit of Commonwealth nations being held in the capital Colombo.
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The normally sedate event has been shaken by the intensifying row over atrocities during the final months of the war and ongoing abuses ever since.
“Let me be very clear. If an investigation is not completed by March, then I will use our position on the UN Human Rights Council to work with the UN Human Rights Commission and call for a full credible and independent international inquiry,” Mr Cameron told reporters.
March is when the UN Human Rights Commission next meets to assess Sri Lanka’s progress on addressing human rights abuses including allegations of war crimes.
It was not immediately clear what form an international inquiry would take.
If an investigation is not completed by March, then I will call for a full independent inquiry – David Cameron
Mr Cameron added: “Ultimately all of this is about reconciliation. It is about bringing justice and closure and healing to this country which now has a chance of a much brighter future. That will only happen by dealing with these issues and not ignoring them.”
The government, run by Mahinda Rajapaksa and several of his family members, disputes the number given for civilian deaths and says civilian casualties were far lower. It says criticism of its record on rights amounts to foreign interference in its affairs.
“We are not going to allow, definitely we will object it,” another one of the president’s brothers, Economic Development Minister Basil Rajapaksa said in response to a question about the possibility of an international inquiry.
On Saturday Channel 4 News Foreign Affairs Correspondent Jonathan Miller quizzed Mr Rajapaksa about Mr Cameron’s earlier comments.
President Rajapaksa replied: “We will take our time and we will investigate into nearly 30 years of war.”
Sri Lanka has in the past refused to allow the United Nations unfettered access to the former war zones.
We will take our time and we will investigate into nearly 30 years of war – Mahinda Rajapaksa
The Sri Lankan army crushed Tamil Tiger separatists in the final battle of a long civil war in 2009, in a strategy partly drawn up by President Mahinda Rajapaksa’s brother, defence secretary Gotabaya Rajapaksa.
Some 300,000 civilians were trapped on a narrow beach during the onslaught and a UN panel estimates 40,000 non-combatants died. Both sides committed atrocities but army shelling killed most victims, it concluded.
Since the end of the war, harassment of government critics, including attacks on journalists and human rights workers have continued.
A heavy army presence on the former Tamil Tiger strongholds in the north of the country angers some local ethnic Tamils who feel they are treated as enemies of the state.
Read more: Cameron 'good to his word' in tackling Rajapaksa on human rights
At the opening ceremony of the Commonwealth meeting on Friday, the president said he had saved lives by ending the war and that the Commonwealth should not be a punitive organisation dominated by “bilateral agendas.”
The Commonwealth groups 53 nations, mostly former British colonies, and is headed by Queen Elizabeth. It has little power or economic clout but sometimes plays a role in resolving disputes.
Sri Lanka had predicted 37 of the Commonwealth’s member nations would attend the summit. In the end, just 26 showed up. The leaders of Canada and Mauritius publicly boycotted the event because of concerns about human rights. India’s prime minister stayed away because of pressure from Indian ethnic Tamils.
Leaders of Commonwealth Heads of Government Meeting (CHOGM) held an informal summit in Colombo on Saturday to discuss the group of nations' future.
The grouping of mostly former British colonies gathered at a waterfront resort in the capital on the second day of the biennial summit that has brought with it intense scrutiny of Sri Lanka's human rights record four years after the civil war ended.
President Mahinda Rajapaksa had hoped the 15-17 November meeting, which two heads of state have boycotted, would prove an advertisement for progress and economic growth in the island state of 21m off India's southern tip.
Instead the summit has been overshadowed by allegations of state-sponsored rape and torture, and political pressure, that has also come from British Prime Minister David Cameron who has vowed to press Sri Lanka on its human rights record.
Earlier on Saturday, Mr Cameron told a news conference that in his meeting with Rajapaksa he pressed for an independent probe into the human rights abuses after his visit to Jaffna, saying that the issue could no longer be wished away.
The British Prime Minister visited the former conflict zone where tens of thousands of civilians died in the last months of a war between the government and the Liberation Tigers of Tamil Eelam (LTTE) rebels, who lost their fight for a separate state for Sri Lanka's Tamil minority.
He was the first international leader to visit the north of the country where the war ended in 2009.
Rajapaksa has staunchly defended his government's record, after saying this week it had "nothing to hide".
Separatist Tamil rebels battled government forces for 26 years until an army offensive crushed them in 2009.
A UN panel has said around 40,000 mainly Tamil civilians died in the final months of the offensive. Both sides committed atrocities but army shelling killed most victims, it concluded.