It was a private conversation and I don't want to go into details about what was said.

那是一段私人谈话，我不想详述所谈内容。

《柯林斯英汉双解大词典》

youdao

youdao

Private conversation. -Yes.

私下聊天，-是。

普林斯顿公开课 - 人性课程节选

Pediatricians try to carve out time for some private conversation, without a parent present, starting around age 10.

WSJ: Young Adults Find It's Hard to Part With the Pediatrician

The meeting is not called for the purpose of a bilateral or a private conversation between the two.

WHITEHOUSE: THE WHITE HOUSE

But we didn't -- I think they wanted to have -- each man wanted to have a private conversation.

WHITEHOUSE: Press Briefing