Secretary of State Condoleezza Rice is moving to quell a revolt among US diplomats angry over moves to force Foreign Service officers to work in Iraq under threat of dismissal. Rice plans to send a cable to all US embassies and missions abroad on Thursday explaining the rationale behind the decision to begin the largest diplomatic call-up since Vietnam, a US official told The Associated Press. The effort comes after a contentious "town hall meeting" at the department on Wednesday in which diplomats expressed serious concerns about being forced to work in Iraq. Rice, who did not attend the meeting, was making clear in the cable that foreign service officers have a duty to uphold the oaths they took to carry out the policies of the government and be available to serve anywhere in the world, according to the official. The official spoke on condition of anonymity because the cable has not yet been sent. It was expected to be released through the department's internal messaging system before Rice leaves on a trip to Turkey and the Middle East later Thursday, the official said.