President Mamadou Tandja has undermined Niger's efforts over the last 10 years to advance good governance and the rule of law, President Barack Obama's spokesman said on Thursday.

In a statement issued in Washington, White House spokesman Robert Gibbs said the U.S. is concerned at Tandja's decision "to rule by ordinance and decree and to dissolve the National Assembly and the Constitutional Court as part of a bid to retain power beyond his constitutionally-limited mandate."

Gibbs said the U.S. is encouraged that the African Union has sent a delegation to Niger to seek to resolve the crisis, and will consult with its partners in the region and monitor Niger closely.