133.(1) Every contract entered into by the [Municipal Commissioner] on behalf of the [Corporation] shall be entered into in such manner and form as would bind him if it were made on his own behalf and may in like manner and form be varied or discharged :
Provided that--
(a) the common seal of the [Corporation] shall be affixed to every contract which, if made between private persons, would require to be under seal, and
(b) every contract for the execution of any work or the supply of any materials or goods which will involve an expenditure exceeding two thousand and five hundred rupees shall be in writing, shall be sealed with the seal of the[Corporation] and shall specify--
(i) the work to be done or the materials or goods to be supplied as the case may be ;
(ii) the price to be paid for such work, materials, or goods ; and
(iii) the time or times within which the contract or specified portion thereof shall be carried out.
(2) The common seal of the [Corporation] shall remain in the custody of the [Municipal Commissioner] and shall not be affixed to any contract or other instrument except in the presence of a [Corporator] [***] who shall attach his signature to the contract or instrument in token that the same was sealed in his presence.
(3) The signature of the said [Corporator] [***] shall be distinct from the signature of any witness to the execution of such contract or instrument.
(4) No contract executed otherwise than as provided in this section shall be binding on the [Corporation].