Talleyrand, as was his invariable practise in these disputes between France and England, left no stone unturned to dissuade his government from embarking upon a course of conduct destined inevitably to revive the old rivalry between the two countries. Were France to break her word and to retain her troops in Belgium, he was convinced that Lord Grey and his colleagues would be driven from office and their successors would be men far less well disposed towards France. Palmerston, he wrote, was assailed by questions in the House and must before long make some definite statement. Sébastiani, in reply, expressed regret for the difficulties by which Lord Grey was beset, but maintained that the French government, were it to allow the army to return home empty handed, would be confronted by a still more unpleasant situation. Talleyrand, however, might announce that, in consequence of the retirement of the Dutch, 20,000 of Marshal Gérard's troops would be recalled and that the remaining 30,000 would be concentrated at Nivelle.[145] The news of this partial evacuation caused much satisfaction in London, but none the less Palmerston, on August 17, instructed Lord Granville formally to demand the complete withdrawal of the French army corps. He was directed to remind the French government of its pledges and to point out that, by the protocol of April 17, the four Powers had agreed to the principle of the destruction of the frontier fortresses, "the satisfactory execution of which arrangement could only be impeded by any measures having the appearance of making the protracted occupation of Belgium by the French army bear upon it. . . ." He was to speak "in terms of friendship and goodwill, enforcing at the same time the just expectations of His Majesty with firmness and decision."[146]