Australian Foreign Minister Julie Bishop was today adamant the informal dinner held at Winston Peters' Auckland home last night was "delghtfull", but Mr Peters added part of the reason was he didn't inflict his own cooking on her.

The pair of Foreign Ministers joked about the dinner at Mr Peters Auckland home in Saint Marys Bay last night which included a late guest - Prime Minster Jacinda Ardern.

Asked whether Mr Peters cooked for his dinner guests he jovially replied: "No, I think Ms Bishop deserves better than that. But I organised it though."

Ms Bishop was quick to turn things back to a sincere tone, saying the private dinner was a sign of the diplomatic closeness of the two countries.

"I think this indicates the closeness of our relationship, the fact that the Deputy Prime Minister invited the Australian delegation to his home and was so gracious in his hospitality, inviting the Prime Minister to his home, shows the depth of our friendship, and it was a very delightful, charming evening," Ms Bishop said.

The dinner between the leaders last night had not been publicised beforehand, and Mr Peters was questioned this afternoon in Auckland over whether it had been intended to be kept secret.

"The reality was we were not going to make the mistake of speaking up before the thing was organised and finalised," Mr Peters said.

"And we didn't know if Jacinda Ardern could make Auckland at a certain time in the evening.

"I sincerely apologise for not telling the press secretary and all those other people, but it happened."

Aside from the food, or scheduling, of the dinner, Ms Bishop also revealed the general topics of discussion.

"We discussed a whole range of things, it was absolutely delightful to meet with her in such an informal and welcoming environment and I really appreciated the opportunity," Ms Bishop said.

"We spoke for a very long time about a whole range of things. As two female politicians we discussed a lot of matters of contemporary interest.

"We also discussed some very serious issues involving Australia and New Zealand so it was a delightful and in depth conversation."

Ms Bishop also begrudgingly revealed a conversation she had with the Prime Minister about her casual shoewear, as seen in an Instagram post of the two of them last night.

"Seriously? Well now that you ask yes we did discuss her footwear," she said.

"She had been at a conference and was dressed casually and she told me that she was wearing a New Zealand brand of footwear, I understand 100 per cent merino wool, and labeled the comfiest shoes in the world.