By Jonathan Beale
BBC News, Washington
US First Lady Laura Bush has urged UN chief Ban Ki-moon to condemn Burma's crackdown on pro-democracy protestors.
The US First Lady Bush has taken a particular interest in Burma
In a rare political intervention, she also called on the UN Security Council to act to prevent further violence.
Her direct intervention shows growing frustration in the White House with the UN's muted response to problem.
President George W Bush has already called for the release of all political prisoners and urged the Burmese government to "stop its intimidation".
The White House issued a statement confirming that Laura Bush had telephoned the UN secretary general to express her deep concern over the deteriorating situation in Burma.
In what can only be seen as a sharp rebuke to Mr Ban, Mrs Bush added that by staying quiet the United Nations, as well as other countries, condoned the abuses.
She also called for the UN Security Council to take unspecified action.
Mrs Bush has taken a particular interest in Burma's political future, meeting dissidents and convening a discussion at a UN General Assembly on the country's future.
She is calling on UN member states to support the Burmese people in their struggle for freedom.