In the winter of 1921, the Greek government decided on a military confrontation with the Turkish nationalist movement led by Mustafa Kemal (later known as Atatürk) which was growing in strength and threatening the Smyrna Protectorate. In March Athens launched a major offensive. The Greek army pushed eastward into Asia Minor along a broad front. At one point the Greek line extended across much of Anatolia. Through 1921, the Greek army met only success, but Kemal retreated skillfully to avoid major defeat. Constantine himself visited the front line, and his younger brother George remained there as a member of the high command. But Greece was now increasingly isolated from its wartime allies. Britain and the United States urged caution and offered to mediate a solution. France and Italy openly supplied arms to the Turks. When Britain and the United States withdrew loans to protest hostilities, Greece's cash resources, and soon ammunition and supplies, were seriously depleted. Internally, the Greek army was fraught with divisions between Venizelists and royalists.