Sri Lanka's President Maithripala Sirisena (Photo: LAKRUWAN WANNIARACHCHI/AFP/Getty Images)

Sri Lanka’s president backed down Wednesday from a refusal to ask the UN rights body for more time to probe war crimes during the island nation’s brutal civil conflict.

Sri Lankan government troops were accused of killing at least 40,000 ethnic Tamil civilians in the final months of the island’s 37-year guerrilla war that ended in May 2009.

A 2015 UN Human Rights Council resolution gave Sri Lanka 18 months to establish a credible investigation. Colombo secured a two-year extension in 2017 that expires this month.

Maithripala Sirisena said last week that he did not want another extension, saying that he did not want to “dig up the past and re-open old wounds.”

This triggered a rift with the government led by Sirisena’s rival Prime Minister Ranil Wickremesinghe, which said it would send a separate delegation to a meeting of the UN rights body in Geneva next week.

Legislator Mahinda Samarasinghe, a spokesman for Sirisena, said the president has now changed his mind.

“I told the President that we can’t have two delegations and that was accepted,” Samarasinghe said. Another solution to the situation was found. “A representative of the president will go to Geneva, but as a member of a delegation headed by the Foreign Minister.”

Top UN diplomats had expressed concern over “worryingly slow” progress by Colombo. Over 100,000 people were killed in Sri Lanka’s 37-year-old Tamil separatist war.

The UN has acknowledged that Colombo made some positive advances on constitutional and legal reforms, limited land restitution and symbolic gestures towards reconciliation.

But it has also cautioned that the measures taken under Sirisena were inadequate, lacked coordination and a sense of urgency.