(CNN) -- Demonstrators around the world plan to show their support for Aung San Suu Kyi at rallies celebrating the pro-democracy leader's 65th birthday Saturday, while international leaders renewed calls for her release.
Suu Kyi, a Nobel peace laureate, has spent 14 of the past 20 years under house arrest in Myanmar, which is also known as Burma.
"I once again call on the Burmese government to release Aung San Suu Kyi and all political prisoners immediately and unconditionally, and to allow them to build a more stable, prosperous Burma that respects the rights of all its citizens," President Obama said in a statement Friday.
Demonstrators planned to call on Obama and members of Congress to do more to demand Suu Kyi's release at a rally in Washington, D.C., Saturday. Other such events were planned around the world this week.
International leaders have marked Suu Kyi's birthday by repeating criticisms of her detention.
"I'm deeply concerned that she is still under house arrest without being released," U.N. Secretary-General Ban Ki-moon told reporters Friday. "I have been consistently -- consistently demanding that all the political prisoners ... should be released without conditions as soon as possible so that they will be able to participate in the political process, since Myanmar is going to have an election this year."
Also Friday, British Foreign Secretary William Hague said Suu Kyi's continued detention "contravenes international human rights law and casts a long shadow over planned elections in the country."
Suu Kyi has been imprisoned or under house arrest repeatedly since 1990, when her party, the National League for Democracy, won a landslide election victory.
The military junta that rules Myanmar never recognized the results. The junta recently passed a law that made her ineligible to stand in the upcoming election because she had a court conviction.
The Nobel peace laureate's current house arrest was extended by 18 months last August after American John Yettaw snuck into her lakeside home uninvited and stayed for two days.
That prompted Suu Kyi to be tried on charges of government subversion. She told the court she didn't know Yettaw, was unaware of his plans to visit and didn't report his intrusion because she didn't want him to get into trouble.
She was sentenced to additional home confinement after being found guilty of violating the terms of her house arrest.