It is hereby expressly agreed and declared by the Parties that notwithstanding any of the provisions of this Agreement to the contrary, the provisions and terms of this Agreement may at any time and from time to time be mutually varied or amended by the Parties by means of a mutual exchange of letters or such other means as the Parties may agree from time to time and thereupon such amendments and variations shall be deemed to have been amended or varied accordingly and shall be read and construed as if such amendments and variations have been incorporated in and had formed part of this Agreement at the time of execution hereof.