Chapter XLIX: Section III: New States and Territories

1ST CLAUSE. New States may be admitted by the Congress into this Union; but no new State 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.

2nd CLAUSE. The Congress shall have power to dispose of and make all needful rules and regulations respecting the territory or other property belonging to the United States; and nothing in this Constitution shall be so construed as to prejudice any claims of the United States or of any particular State.