YANGON (Reuters) - Myanmar opposition leader Aung San Suu Kyi spent her 64th birthday in detention on Friday as supporters worldwide condemned her trial and called for tougher sanctions against the military regime. The Nobel laureate marked the day by sharing a meal of chicken biryani with staff at Yangons Insein prison, where she is on trial and faces up to five years in jail if found guilty of violating her house arrest. She will invite doctors who care for her, some guards and others to her party, Dr Win Naing, a senior member of her National League for Democracy (NLD), told Reuters. Confined for more than 13 of the past 20 years, Suu Kyis birthday has become an annual ritual inside and outside Myanmar for campaigners seeking an end to decades of military rule that has left the country an impoverished international pariah. The day took on added significance this year amid international outrage at the trial, which is widely expected to deliver a guilty verdict. Pro-democracy activists planned protests and events in 20 cities around the world. They also launched campaigns on social networking sites such as Facebook and Twitter. Another online campaign, www.64forsuu.org, drew thousands of messages of support, including good wishes from Hollywood star Julia Roberts, U2 frontman Bono, footballer David Beckham and British Prime Minister Gordon Brown. Aung San Suu Kyi is an inspiration to her country and the rest of the world, wrote former Beatle Paul McCartney. I truly admire her infallible resolve and her determination to stand up for what she believes in. Suu Kyi is accused of breaking the terms of her house arrest by allowing an American intruder, John Yettaw, to stay for two days after he swam to her Yangon home in early May. Suu Kyis two female housemates and Yettaw are also charged with breaking the countrys draconian security laws. Critics say the trial is aimed at excluding Suu Kyi from next years elections, which they dismiss as a sham to entrench nearly half a century of military rule. UN investigators say the trial has been marred by flagrant violations of substantive and procedural rights. Most of it has been held behind closed doors and favoured the prosecution, which called 14 witnesses against two for Suu Kyi. Myanmars High Court said on Friday it would hear Suu Kyis bid to reinstate two other defence witnesses on June 24. In London, British Foreign Office Minister Ivan Lewis called the charges ridiculous and said the European Union would consider more sanctions against the junta after the trial ended. We (Britain) continue to believe that further targeted financial sanctions would increase pressure on the regime, he told reporters. The West has tried sanctions for years but failed to force reforms from the generals. Neither has a policy of engagement favoured by Myanmars Asian neighbours. In Yangon, about 200 Suu Kyi supporters gathered at the NLDs dilapidated headquarters to call for her release. They freed birds, coloured balloons and sang birthday songs. Im really worried about her health, said 62-year-old Daw Tin Hla. Everything would be gone without her. The NLD, denied power after winning a landslide election victory in 1990, repeated calls for the release of Suu Kyi and more than 2,000 other political prisoners. It will most likely fall on deaf ears as the regime presses ahead with its roadmap to democracy and seeks to silence dissent in the run-up to the 2010 polls. Britains ambassador to Myanmar, Mark Canning, speaking to reporters in London by video link from Yangon, said there was no doubt Suu Kyi would be found guilty. But she would probably be sentenced to a further period of house arrest, rather than jail.