ACT leader Rodney Hide is engaged to his girlfriend Louise Crome.
Mr Hide confirmed the engagement to Ms Crome, 32, a former competitive squash player, to the New Zealand Herald.
"I fully accept my actions as a politician are quite properly open to public examination, but Louise and I are hoping to keep our private life just that, out of the public eye."
The pair have been together since 2007.
Mr Hide, 53, and his former wife Jiuan Jiuan Kok divorced earlier this year after separating in 2007. They had been married about 24 years.
Ms Kok told the newspaper she wished the couple well but wanted Mr Hide to make a financial settlement.
"It was very easy for the man to pack up and leave, but for the wife who helped him, his career, looked after his family - he was largely an absentee father and husband. I did my best for him and his career."
Mr Hide's relationship hit the headlines last year after he took Ms Crome with him on taxpayer-funded trips to Europe and Hawaii. He apologised and repaid $22,000.
NZPA