She is currently being held in Yangon's Insein prison and faces trial on Monday.

If convicted, the democracy activist and Nobel Peace Prize winner faces five years in jail, which would stretch her detention past its expiry date of May 27 and beyond the 2010 elections.

Health concerns

In depth

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Suu Kyi was placed on an intravenous drip at her house on Friday by Myo Win's medical assistant because she could not eat, had low blood pressure and was dehydrated.

Suu Kyi's National League for Democracy (NLD) party said it was aware of the development.

"I also heard about his release but I haven't had any contact with [Myo Win] yet," Nyan Win, the NLD spokesman, told the AFP.

It was not clear if Myo Win would be allowed to visit Suu Kyi.

New charges

The charges follow an incident in which an American man swam across a lake to her home and stayed there secretly for two days.

"I have determined that it is necessary to ... maintain in force the sanctions against Burma"

Barack Obama, US president

Suu Kyi's lawyer said John Yettaw, 53, had not been invited and that she had tried to send him away.

Western governments were quick to condemn the new charges against Suu Kyi and called for her immediate release.

Gordon Brown, the British prime minister, said on Friday that if "the 2010 elections are to have any semblance of credibility, she and all political prisoners must be freed to participate".

Extended sanctions

Barack Obama, the US president, formally extended US sanctions against Myanmar in a move aimed to increase pressure on the military government to drop the new charges.

Suu Kyi's lawyer said that Yettaw, pictured, had not been invited to visit her [EPA]
"I have determined that it is necessary to continue the national emergency with respect to Burma and maintain in force the sanctions against Burma to respond to this threat," Obama said in a message to congress on Friday.

Hillary Clinton, the US secretary of state, has said that she wants to find a "better way" to sway Myanmar's military leaders.

Foreign ministers of the European Union last month also extended their sanctions against Myanmar for another year, but said they were ready to ease them and hold talks if there was democratic progress.

Suu Kyi was detained after her party's landslide victory in the country's general election in 1990 and has been under house arrest for much of the past 19 years.