The States Reorganisation Act,1956
Section 21. Functions of the Councils
(1) Each Zonal Council shall be an advisory body and may discuss any matter in which some or all of the States represented in that Council, or the Union and one or more of the States represented in that Council, have a common interest and advise the Central Government and the Government of each State concerned as to the action to be taken on any such matter.
(2) In particular, and without prejudice to the generality of the provisions of sub-section (1), a Zonal Council may discuss, and make recommendations with regard to,-
(a) Any matter of common interest in the field of economic and social planning;
(b) Any matter concerning border disputes, linguistic minorities or inter-State transport; and
(c) Any matter connected with, or arising out of, the reorganisation of the States under this Act.