The UN special representative to Myanmar said yesterday that he had quit his post after being refused entry to the military-ruled country, where he is pushing for reforms, for nearly two years.
Former Malaysian diplomat Razali Ismail, who has been trying to break Myanmar's political impasse since 2000, said he would not renew his contract which lapsed at the end of last month.
"My contract lapsed after December 2005. It is clear they [the military junta] do not want me back," Razali said.
"I have not been allowed to visit the Myanmar leadership in Yangon in the past 22 months," he added.
He said the UN had accepted his decision.
"So it is time for me to make an exit," he said.
Razali was the catalyst for the landmark contact between the Myanmar government and the jailed pro-democracy leader, Nobel Peace Prize-winner Aung San Suu Kyi, which began in October 2000.
But he had recently admitted that negotiations were foundering and expressed little confidence that Aung San Suu Kyi would be released.
He said the 10-nation regional body, the ASEAN, should take a tougher line against the former British colony.
"ASEAN should talk more, persuade or even cajole the government," Razali said.
However, initial results have not been promising with Myanmar on Friday putting off an expected visit by ASEAN envoy Syed Hamid Albar, Malaysia's foreign minister, because it is relocating its capital.
Razali expressed disappointment with the development but warned of further delays.
"I think Syed Hamid's visit is in line with ASEAN's aspirations. I think more delays could be expected," he said.
Myanmar Foreign Minister Nyan Win refused to set a date for Syed Hamid's visit, which was agreed at an ASEAN summit last month.
Myanmar joined ASEAN in 1997 but is often a source of embarrassment for the regional body, which is frequently urged to press it for democratic and human rights reforms.
The country's military took power in 1988 after crushing massive pro-democracy street demonstrations, but refused to hand power to Aung San Suu Kyi's National League for Democracy party after it won the 1990 general elections.
The junta is holding a national convention to draft a constitution that would allow a return to civilian rule. But no timetable has been set, and Aung San Suu Kyi's party is boycotting the process because of her continued detention.
In November, the junta announced it was moving the government to Pyinmanar, a logging town 320km north of Yangon.
Speculation about the reason for the relocation ranges from the government's fear of a US invasion to astrological predictions and worries over possible urban unrest in Yangon.