Karen National Union (KNU) core member David Thaw passed away on Sunday night in a military hospital in Yangon, according to Karen in exile.
Thaw, aged 65, secretary of the KNU Peace Committee and key member of the negotiating team with the Myanmar government, died in Mingaladon Hospital, considered the best hospital in town, Myanmar activists said.
The news was broken on Monday morning by Ko Ko Lay, a United States citizen and a former Myanmar student leader, at a press conference in Bangkok to explain a trip by Myanmar exile activists dubbed the Peace Delegation for Motherland.
"The minority KNU disagree with the pace of the peace talks, so they will likely split. But we hope the KNU could later on enter some agreement with the government, because if war continues it is the people who will be affected," said Ko Ko Lay, former information secretary of the All Burmese Students Democratic Front (ABSDF), the largest youth organsation on the Thai-Mynamar border in the post 1988 crackdown.
Thai intelligence sources confirmed the report, saying his death did not seem to be suspicious. He suffered from severe illness and had been in poor health.
"He had only 17% functioning of his lungs. He was treated for two or three days in the military hospital, but the blood transfusions failed to stabilise his condition," the Thai sources said.
The KNU has been in peace talks with the Nay Pi Daw, the Myanmar military, since January 2012. Thaw had tried to push the pace of the talks and set up a unit outside the KNU stronghold in Manerplaw, opposite Tak's Tha Song Yang district.
The liaison office in Pa-an was not recognised by the KNU central committee and the move was disowned as it was Thaw’s lone decision, sources said.
The KNU has suffered some setbacks since the death of charismatic leader Bo Mya in December 2006 in Tak province. The KNU is still run in a collective manner by David Tharckabaw, Ms Naw Ziphorah and others.