"A cease-fire means that both sides have to stop fighting. Right now, even if Zelensky agrees to negotiate, there is no evidence that Putin wants to negotiate, that he wants to stop fighting, or that he has ever wanted to stop fighting. And yes, according to Western officials who have periodic conversations with their Russian counterparts, attempts have been made to find out."
On Putin's waiting game:
https://www.theatlantic.com/ideas/archive/2023/11/us-ukraine-support-putin-defeat/675953/