The United Nations envoy to Burma has begun a fresh visit to Rangoon reportedly frustrated by the country's lack of democratic reform.

Malaysian diplomat Razali Ismail helped broker landmark talks in October 2000 between the military junta and the opposition leader Aung San Suu Kyi.

Mr Razali is expected to meet Than Shwe, Burma's top leader

But the talks have made little progress since May when Aung San Suu Kyi was released from 19 months of house arrest.

Mr Razali will be meeting both sides during his five-day visit, including the junta's top leader General Than Shwe.

Western pressure

Mr Razali is thought to be deeply disappointed that the junta has released just a handful of the more than 1,000 political prisoners believed to be in Burma's jails.

He hinted at his frustration with the lack of progress in an interview with Reuters news agency before his departure.

"I do not want to be the special envoy that wanders around for 15 years doing things with no light at the end of the tunnel," he said.

The United States and European Union have issued separate statements urging the Burmese junta to move towards reform.

"Given such a positive step earlier this year, we expected that dialogue between the regime in Burma and Aung San Suu Kyi would be underway by now," said State Department spokesman Richard Boucher.

United Nations Secretary-General Kofi Annan also expressed his concern that the momentum generated by the opposition leader's release "could dissipate, unless some tangible progress is made in the near future".

Aung San Suu Kyi's National League for Democracy overwhelmingly won 1990 elections but the military government refused to hand over power.

The Burmese Government is under pressure to reform as the economy is in crisis and it badly needs foreign aid.