The Burmese authorities arrested 20 followers of the democracy leader and Nobel Peace Prize winner Aung San Suu Kyi, as they prolonged her house arrest for another six-month period.

Government officials entered the cordon of police and barbed wire barricades around Ms Aung San Suu Kyi's house, and presented her with the extension order. Despite never being convicted of any crime, she has spent 12 of the past eighteen years in detention, after her National League for Democracy (NLD) won an overwhelming victory in a general election in 1990.

Today, 30 members of the NLD youth wing rallied in front of the party's headquarters in the former capital, Rangoon, but most of them were arrested as they attempted to march to the home of "the Lady", as she is known in Burma, on University Avenue.

Ms Aung San Suu Kyi's present period of incarceration began after a convoy of her and her party members was ambushed close to the Burmese ton of Depayin in 2003. Government thugs killed a number of her supporters and she was placed in detention "for her own protection".

Lawyers acting on her behalf insist that, even according to the junta's own laws, today's move is unjustifiable. Five years is the maximum period of house arrest - beyond that, there must be new grounds for detention.

It was not clear last night if these had been cited in the envy order. But the Burmese junta finds itself under unusually little international pressure on the detention of Ms Aung San Suu Kyi, thanks to the humanitarian disaster caused by Cyclone Nargis.

Last weekend, ministers and officials from 50 countries joined the United Nations Secretary General Ban Ki Moon in Rangoon at a conference to discuss aid for the 2.4 million surviving victims of the cyclone. Burma's Senior General Than Shwe has agreed to allow foreign aid workers into the country on condition that aid is not "politicised". In practise, this means that the name of Ms Aung San Suu Kyi is not to be mentioned for fear of jeopardising international access to the needy victims of the storm.

UN agencies and international charities report that the change in policy towards foreign aid workers has not yet made any dramatic change on the ground. "We're testing it, and we don't know yet what it's going to mean in practice," Hakan Tongul of the UN's World Food Programme told Times Online.

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