(1) Save as provided in this Act (a) no sale (including sales in execution of a decree of a Civil Court or for recovery of arrears of land revenue or for sums recoverable as arrears of land revenue), gift, exchange or lease of any land or interest therein, or (b) no mortgage of any land or interest therein, in which the possession of the mort gaged property is delivered to the mortga gee, shall be valid in favour of a person who is not an agriculturist (or who being an agricul turist will after such sale, gift, exchange, lease or mortgage, hold land exceeding two thirds of the ceiling area determined under the Maharashtra Agricultural Lands (Ceiling on Holdings) Act, 1961 or who is not an agri cultural labourer): Provided that the Collector or an officer authorised by the State Government in this behalf may grant permission for such sale, gift, exchange, lease or mortgage, on such conditions as may be prescribed . . " It may be mentioned that the conditions alluded to in the proviso to the above quoted section 63 have been pre scribed by Rule 36 514 of the Bombay Tenancy and Agriculutral Lands Rules, 1956 (hereinafter referred to as 'the Rules ') the relevant por tion whereof is to the following effect: "36.