law: The Haryana and Uttar Pradesh (Alteration of Boundaries) Act, 1979
  4. Transfer of territories.-
  (1) As from the appointed day,-
  (a) there shall be added to the State of Haryana all the territories of the State of Uttar Pradesh which lie on the Haryana side of the fixed boundaries, and the said territories shall thereupon cease to form part of the State of Uttar Pradesh; and
  (b) there shall be added to the State of Uttar Pradesh all the territories of the State of Haryana which lie on the Uttar Pradesh side of the fixed boundaries, and the said territories shall thereupon cease to form part of the State of Haryana.
  (2) Each of the State Governments of Haryana and Uttar Pradesh shall, by order in the Official Gazette of the State, provide for the administration, as from the appointed day, of the territories transferred to that State under sub-section (1) by including them or any part of them in such district, sub-division, police-station or other administrative unit as may be specified in the order.