If nukes were not used against Berlin (by either side), then the forces in West Berlin could probably have held out for some time. There's a thread somewhere from a few years back were a few of us posted some info about the stockpiles that the West Berlin government had put in place - food, electricity, water, fuel and so on.
West Berlin, being completely cut-off by the Soviets from electricity from West Germany in 1952, developed a long-term plan for its own power supply and part of that plan was
one years worth of natural gas. They were already isolated by the Soviets so it wasn't much more of an effort to put longer term stockpiles in place.
The specific links are on the second page posted by RN7 (post #43) and myself (post #55).
I've also added "berlin" and "west berlin" to the tags for that thread so hopefully it'll be easier to find in the future. I wanted to add "stasi" as well but we're limited to just two tags each it seems
As an aside, Jason Weiser was one of the contributors to the thread.
https://forum.juhlin.com/showthread.php?t=5244