sticking point
noun [ C ] uk/ˈstɪk.ɪŋ ˌpɔɪnt/ us/ˈstɪk.ɪŋ ˌpɔɪnt/
（讨论的）阻塞点，分歧点;症结
A sticking point in a discussion is a point on which it is not possible to reach an agreement
Exactly how the land is to be divided up is the main sticking point of the peace talks. 土地究竟该如何分割是和谈的主要分歧点。