Foreign Minister Murray McCully is off work for a few weeks after surgery in Auckland last week.
Prime Minister John Key has assumed responsibility for his foreign affairs portfolio.
The surgery is thought to have removed a potentially cancerous growth in his abdomen but which has proven to be benign.
He is at home but his recovery means he will miss the Apec meeting of foreign ministers in Manila this month.
Mr McCully has been MP for East Coast Bays since 1987.
He is aged 62.