Why delhi is not a state?

Delhi is a Union Territory it does not belong to any state. Union Terriotories are under the direct Control and Supervision of the Central Government.
There are 7 such union Territories in India which are directly governed by the Central Govt.

Union Territories do not have any state Government like regulatory body.
Now there's a rumor spread that delhi will become a state and the count of state in India will go to 29

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