The survey by the service's union, the American Foreign Service Association (AFSA), revealed serious staff complaints with salaries and other personnel issues as well as staffing at the US embassy in Iraq.

"The survey reveals deep frustration by our nation's career diplomats with their lack of resources with which to do their jobs," the AFSA said in a statement to the media.

Only 18 per cent of the nearly 4,300 respondents to the survey said Rice was doing a good or very good job defending their profession, compared to 44 per cent who thought she was doing a poor or very poor job.

Thirty-eight per cent rated her as doing a fair job.

Only 14 per cent thought she was doing a good or very good job in securing resources for the Foreign Service, compared to 49 per cent who thought she was doing a poor or very poor job.

Some 36 per cent said her performance was fair.

The top concern was so-called overseas comparability pay, AFSA said in an article in the monthly Foreign Service Journal.

"Numerous respondents expressed outrage that they now have to accept close to a 20-per cent cut in base salary when they leave Washington to serve overseas, while senior officers and employees of other US agencies do not."