New Zealand half-back Aaron Smith has issued a tearful apology after being caught having sex in a disabled toilet last month.

The 27-year-old was suspended by the All Blacks for one game after he spent "five to 10 minutes" with a woman in a toilet at Christchurch Airport on Sunday, September 18, the day after the All Blacks' victory over South Africa.

Speaking to reporters in Durban on Thursday, an emotional Smith said: "I've made a huge mistake, a huge error in judgment. I'd firstly like to say a huge sorry to my partner Teagan, her family, my family. I'm also sorry to my teammates, NZRU and the New Zealand fans.

"My behaviour was unacceptable and if you could respect me and my partner in this situation ... I'm just trying to get home to deal with this. Thank you."

The suspension means that Smith will miss the All Blacks' Rugby Championship match against South Africa in Durban on Sunday.