The organisations have been speaking out after King Jigme Singye Wangchuck allowed the Bhutanese national assembly to acquire new powers enabling it to force him to abdicate.

Under the new rules, the king will have to stand down in favour of the crown prince if there is ever a two-thirds majority in the assembly for him to go.

King Wangchuck has also given the assembly the right to elect the majority of members in the country's cabinet.

'A total farce'

One of the two exiled opposition groups, the United Front for Democracy in Bhutan - which predominantly represents the country's majority Buddhist community - has denounced the changes.

Its spokesman, CB Dahal, says the king has made sure that all his trusted family members remain in all the important positions of power.

"So it's purely a total farce, and there is nothing which we believe that's really democratic which is going to come out of this," he said.

'A very good gesture'

However, the Bhutanese Appeal Movement Co-ordinating Council - the voice of the country's minority Nepali speaking community - has given a more positive response.

The council's spokesman, Ratan Gazmer, says the reform could help improve the plight of around 100,000 refugees - mostly of Nepalese origin - who have left Bhutan and are now living in camps in Nepal.

"I think it's a very good gesture on the part of the government of Bhutan to have made these changes," he said.

"We hope that these changes will also reflect on the future of the Bhutanese refugees. If that happens, then I would say that this is a positive move."

Assembly's composition unchanged

BBC correspondents say King Wangchuck is making the changes because he wants to institutionalise checks and balances in the kingdom's political system.

However, the reforms have not affected the indirect election of the national assembly.

Two-thirds of the assembly's 150 members are chosen by district councils. The remainder are appointed by either the king or the Buddhist clergy.

The correspondent says that the disunity of the Bhutanese opposition is likely to please royalist supporters who form the majority in the assembly. But he adds that their main concern is to stop the king from giving up more of his powers.