WASHINGTON, Oct 22 (Reuters) - U.S. President George W. Bush spoke to Iraqi Prime Minister Nuri al-Maliki and Turkish President Abdullah Gul on Monday about efforts to stop Kurdish rebel cross-border attacks, the White House said. Bush and Maliki, speaking by secure video-link, "agreed to work together, in cooperation with the Turkish government, to prevent the PKK from using any part of Iraqi territory to plan or carry out terrorist attacks," White House spokesman Gordon Johndroe said after Kurdish rebels killed at least a dozen Turkish soldiers in fighting over the weekend.