(1) The Commissioner may, on the recommendation of the Board, by executive instrument proclaim any monument which does not belong to the State to be a national monument:

Provided that before making a recommendation under this paragraph the Board shall give not less than two months' written notice of its intention to make the recommendation to the owner or person in control of the monument, who may lodge with the Board objections in writing to the proposed recommendations; and the Board, when making any such recommendation, shall submit to the Commissioner evidence that the owner or person in control has received such notice, together with any objections lodged against the recommendation.

(2) The Commissioner may by executive instrument proclaim any monument which belongs to the State to be a national monument.