When the certificate of the Clerk shows the petition to be sufficient in valid signatures, the Clerk shall submit the proposed ordinance to the Council at its next regular meeting, and the Council shall at once read and refer the same to an appropriate committee, which may be the committee of the whole. Thereafter, the committee shall report the proposed ordinance to the Council with its recommendations thereon not later than the third regular meeting of the Council following that at which the proposed ordinance was submitted to the Council by the Clerk.