(1)  Notwithstanding anything contained in this Act, an agreement may be entered into--

   (a)  by two or more Governments of contiguous States, or

   (b)  by the Central Government (in respect of one or more Union territories) and one or more Governments of States contiguous to such Union territory or Union territories,

to be in force for such period and to be subject to renewal for such further period, if any, as may be specified in the agreement to provide for the constitution of a Joint Board,--

   (i)  in a case referred to in clause (a), for all the participating States, and

   (ii)  in a case referred to in clause (b), for the participating Union territory or Union territories and the State or States.

   (2)  An agreement under this section may--

   (a)  provide, in a case referred to in clause (a) of sub-section (1), for the apportionment between the participating States and in a case referred to in clause (b) of that sub-section, for the apportionments between the Central Government and the participating State Government or State Governments, of the expenditure in connection with the Joint Board;

   (b)  determine, in a case referred to in clause (a) of sub-section (1), which of the participating State Governments and in a case referred to in clause (b) of that sub-section, whether the Central Government or the participating State Government (if there are more than one participating State, also which of the participating State Governments) shall exercise and perform the several powers and functions of the State Government under this Act and the references in this Act to the State Government shall be construed accordingly;

   (c)  provide for consultation, in a case referred to in clause (a) of sub-section (1), between the participating State Governments and in a case referred to in clause (b) of that sub-section, between the Central Government and the participating State Government or State Governments either generally or with reference to particular matters arising under this Act;

   (d)  make such incidental and ancillary provisions, not inconsistent with this Act, as may be deemed necessary or expedient for giving effect to the agreement.

   (3)  An agreement under this section shall be published, in a case referred to in clause (a) of sub-section (1), in the Official Gazette of the participating States and in a case referred to in cause (b) of that sub-section, in the Official Gazette of the participating Union territory or Union territories and participating State or States.