Claude was a commissioner for the Anglo-French Treaty of Ardres, also known as the Treaty of Camp, which was signed on 7 June 1546 and a step towards the conclusion of the Italian War of 1542–1546.[5] After a delay which the English found frustrating, Claude then visited England as a special ambassador for the peace treaty 20–30 August 1546.[6] Four cannon at Walmer Castle burst while firing his salute.[7] Claude wrote from London to his ally, Mary of Guise, in Scotland on 28 August, explaining his difficulties in forwarding their mutual interest.[8]