State Government
When a Bill is reserved by a Governor for the President's consideration, the President shall assent or withhold assent - provided that, for a non-Money Bill, the President may direct the Governor to return it to the State Legislature for reconsideration within six months, after which it must be presented to the President again if re-passed.
Once a Governor reserves a state Bill for the President, the final decision rests with the President (in practice, the Union government) - who can either approve it, reject it, or send it back to the state Legislature for reconsideration within a defined six-month window.
This is why a state Bill reserved by the Governor can end up delayed for a long time or even indefinitely, since there is no fixed deadline by which the President must actually decide whether to assent to or withhold assent from the reserved Bill itself (only the six-month window applies to a Bill sent back for reconsideration).