Staff at the US Centers for Disease Control and Prevention have been ordered to stop communicating with the World Health Organization, according to a new memo, dealing a significant blow to global health efforts.

Federal health officials have been instructed to temporarily stop any “external communications” to the public, according to two officials with knowledge of the situation.

Health officials at the Center for Disease Control have reportedly been ordered to stop working with the World Health Organization, following Trump's criticisms on the agency.