WASHINGTON — The State Department is warning American diplomats they may be forced to serve in Iraq next year and says it will soon start identifying prime candidates for jobs at the Baghdad embassy and outlying provinces, according to a cable obtained yesterday by the Associated Press.

A similar call-up notice last year caused an uproar among foreign service officers, some of whom objected to compulsory work in a war zone, although in the end the State Department found enough volunteers to fill the jobs.

Now, the State Department anticipates another staffing crisis. As a result, the unclassified April 8 cable says, “the prime candidate exercise will be repeated” next year, meaning the State Department will begin identifying American diplomats qualified to serve in Iraq and who could be forced to work there if they don’t volunteer. The prime candidate list will be comprised of diplomats who have special abilities that are needed in Iraq, such as Arabic language skills, deep Mideast knowledge, or training in specific areas of reconstruction.

The cable said more details will be announced next month, but identification of prime candidates is the first step in implementing so-called “directed assignments.” That means ordering diplomats to work in certain locations under threat of dismissal unless they have a compelling reason, such as a health condition, that would prevent them from going.

Elsewhere, Secretary of State Rice yesterday defended the commitment of the nation’s diplomats, despite recent resistance by many foreign services officers to a proposal to require tours in Iraq. The top Republican on the House Armed Services Committee, Rep. Duncan Hunter of California, said he thought the protests last fall against a mere four dozen vacancies for the heavily fortified embassy in Baghdad was pathetic considering the lengthy combat tours by service members. In response, Ms. Rice said the comments made were isolated and prompted a visceral response by the rest of the diplomatic corps, including those serving in dangerous posts outside Iraq and Afghanistan. “I will tell you, the blogs were lit up in the Department of State by people who were offended … who were absolutely offended by those comments,” she said.