Russia agrees and immediately stops supplying arms and support to the separatists who will be allowed to leave Ukraine and go to Russia.
UN SC puts forces in Crimea to stop the ethnic cleansing of the Tartars. This will require that Russia not veto the UN SC resolution and that it cooperate with the UN force.
Ukraine restores water and utility services to Crimea. UN border control established in Crimea including Kerch and other ports to control military traffic to Crimea. Food and other necessities allowed to be re-supplied. Russian forces reduced to pre-February levels.
A period of stability passes at the end of which, the UN holds a plebiscite in Crimea for the residents who lived there before February 2014.
The choices offered in the plebiscite will be 1) Russian annexation, 2) return to Ukraine, or 3) independent autonomous Crimean state. The vote will be final and controlling and affirmed by the Ukraine and Russian parliaments. Russian navy will be granted 15 year extension on any naval lease rights if the choice is Ukraine or independent Crimea.
Russia pays damages for the destruction it caused in East Ukraine. EU and US also continue to contribute to rebuild Ukraine economy.
Ukraine and NATO agree to defer any discussion of NATO membership for up to five years. The parties agree to consider Ukrainian neutrality as a way to avoid future conflict. Violation by Russia of Ukrainian sovereignty and NATO related agreement terminates.
When the conditions above are met, all sanctions shall terminate.