Updated

The U.S. ambassador to Romania says he is "deeply concerned" about threats to the "independence of democratic institutions" in the eastern European country, where the prime minister and the president are engaged in a bitter power struggle.

Soon after Mark H. Gitenstein's comments Tuesday, Romanian lawmakers ousted the Senate speaker, an ally of President Traian Basescu.

The ousted speaker, Vasile Blaga, is to be replaced with an ally of Prime Minister Victor Ponta. Ponta-supporting lawmakers also want to replace the Chamber of Deputies speaker, another Basescu ally.

Gitenstein, the U.S. envoy, says he is especially concerned about the integrity of Romanian courts.

That was an apparent reference to Ponta's decision to defy a Constitutional Court's ruling that Basescu, not he, should represent Romania at a recent European Union summit.