The chief executive of the New Zealand Ministry of Foreign Affairs & Trade, John Allen, is resigning to head up the New Zealand Racing Board.

Allen will join the Racing Board as its chief executive in March, after end his five-and-a-half years heading the government department in Januaray, MFAT said in a statement. He will take over from Stewart McRobie, who has acted in the role since July when Chris Bayliss quit.

"It's going to be fun," said Allen in a Racing Board statement announcing his appointment. "The NZ Racing Board is a $2 billion business that plays a vital role in the New Zealand economy by supporting the racing and sport industries. It is also the owner and operator of the TAB which is an exciting commercial enterprise and an iconic New Zealand brand."

Allen took up the MFAT role in July 2009 and headed a controversial restructuring of the government department which was opposed by many staff and saw 49 ambassadors and heads of foreign missions co-sign a letter criticising the plan. Prior to his role at MFAT, Allen was chief executive of New Zealand Post and was previously a partner of law firm Rudd Watts and Stone.

Allen's departure was flagged by political newsletter Trans-Tasman, which said he planned to announce next Monday that he is leaving for a top post in the private sector. That announcement was brought forward to today.

MFAT is yet to appoint an acting chief executive.