Yep, the Constitution clearly states that in order for an area to secede from a state and form a new state, the area must have permission from the state.
Art 4, Sec 3
but no new States shall be formed or erected within the Jurisdiction of any other State; nor any State be formed by the Junction of two or more States, or parts of States, without the Consent of the Legislatures of the States concerned as well as of the Congress.
Rats. Virginia republicans won’t be able to join with WVa. Pity.