While the campaign in the Southwest Pacific continued, U.S. forces launched an offensive in the Central Pacific, beginning with the November 1943 Battle of Tarawa. The U.S. next captured Japanese positions in the Marshall Islands and the Caroline Islands. In June 1944, the U.S. launched an attack on Saipan, in the Mariana Islands, gaining control of the island in early July at the cost of fourteen thousand casualties. As the Battle of Saipan continued, the U.S. won a major naval victory in the Battle of the Philippine Sea, sinking three Japanese aircraft carriers. In July 1944, Roosevelt met with Nimitz and MacArthur, where he authorized the continuation of the campaigns in the Southwest Pacific and the Central Pacific. MacArthur's force would continue its advance towards the Philippines, while the Central Pacific campaign would work its way towards Japan. The U.S. landed on the Philippine island of Leyte in October 1944, provoking a Japanese naval response, as the Philippine Islands maintained a critical position on the Japanese oil supply route from the Dutch East Indies. The Japanese navy was decimated in the resulting Battle of Leyte Gulf, which is sometimes claimed to be the "largest naval battle in history." MacArthur's forces secured control of Leyte in December and had largely re-taken control of the Philippines by March 1945.