Putin stated that the Istanbul agreements are still valid as the basis for negotiations.
The agreements are reported to have included clauses demanding that Ukraine adopt a geopolitically neutral status and not join NATO, limit the size of its armed forces and special status for Donetsk and Luhansk
We are rapidly approaching the part of things where he will take what we damn well give him.
One of the problems with Russia's "great powers get to do whatever they want" school of foreign policy is that when you grind yourself into a lesser power you do what you're damn well told. And they will.