The White House is defending Health Secretary Robert F Kennedy Jr after a chaotic week at the US Centers for Disease Control (CDC) that led to calls for his removal.

On Friday, White House Deputy Chief of Staff Stephen Miller called Kennedy, also known as RFK Jr, "a crown jewel of this administration".

Earlier this week, CDC Chief Dr Susan Monarez was fired because she was "not aligned with the president's agenda", the White House said in a statement, and was replaced by RFK Jr's deputy Jim O'Neill.

At least three senior CDC leaders have since resigned over frustrations about Kennedy's leadership and vaccine policy. The unease led to some lawmakers calling for his resignation.

Miller called Kennedy "one of the world's foremost voices, advocates and experts on public health", and said he is working hard to restore the credibility and the integrity of CDC, which is one of the world's most foremost public health bodies.