Petrie, who arrived in Myanmar in 2003, had publicly criticised Myanmar's government and will probably have to leave following the decision.

A statement by the UN last month criticised a "deteriorating humanitarian situation" in the country.

Internet blocked

Internet connections in Myanmar, which had been cut on Thursday, were still not operating on Saturday.

On a previous visit, Gambari held talks
with Suu Kyi, who is under house arrest

The restrictions on internet access have been widely seen as an attempt by Myanmar's rulers to limit the flow of information before Gambari's visit, his second in a month.

Gambari is seeking to persuade Myanmar's ruling generals to instigate political reforms, weeks after a violent military crackdown on pro-democracy protesters.

He is expected to meet generals and other senior officials in the capital Naypyidaw, as well as representatives of non-governmental organisations, a Myanmar official said.

 

He will also meet detained pro-democracy leader Aung San Suu Kyi and  members of her National League for  Democracy (NLD) party, the official told AFP news agency.

 

Threat to dialogue

 

Some experts said international scrutiny faced by Myanmar's government could lead to a meeting between Suu Kyi and Than Shwe, Myanmar's ruling general.

However, Larry Jagan, a Myanmar analyst, told Al Jazeera that the decision to end Petrie's mandate in Myanmar was an attempt to derail Gambari's mission to promote dialogue between the government and Suu Kyi's party.

"While it is certainly true that the Burmese regime is very upset with the UN at the moment, paticularly Mr Petrie and the UN country team which were very critical of the government's development programme ... I think the timing is an attempt to sabotage Mr Gambari's visit," he said.

"They want him to deal with [the Petrie] issue and to side-step attempts at getting dialogue between Aung San Suu Kyi and the military regime. I think it really is intentional."

The US has denounced the decision to end Petrie's mandate.

US 'outrage'

"The United States is outraged that the Burmese junta would expel the UN human rights representative," Gordon Johndroe, US national security council spokesman, said, referring to Myanmar's former name of Burma.

Most of those arrested during the protests against the government in September were allied to Suu Kyi.

Suu Kyi has faced several protracted spells under house arrest in recent years, after the ruling generals ignored a win for the NLD in a general election in 1990.

Earlier this week, the government released 165 pro-democracy activists who were arrested during the peaceful protests, which were led by Buddhist monks.

Hundreds more people rounded up during the military's crackdown on the protesters remain in prison.