Zambian President Edgar Lungu has dismissed Health Minister Chitalu Chilufya with immediate effect, the president's office said on Sunday, without giving a reason for the move.

Once seen as a potential presidential replacement for Lungu, Chilufya's political ambitions have faded amid growing calls for his dismissal from opposition parties and health workers.

"The President has thanked Dr Chilufya for the services rendered to government and wished him well in his future endeavours," the office said in a statement.

Chilufya, health minister since his appointment in 2016, was not immediately available for comment.