The US military has had to spend about $200m (£106m) on replacing service members lost under its policy on homosexuals, a report has found.
The issue of homosexuals in the military is highly divisive in the US
The service lost almost 10,000 gays and lesbians under its "don't ask, don't tell" policy, said the study by the Government Accountability Office (GAO).
A number of those had skills - such as languages in Arabic, Farsi and Korean - vital to the US war on terror.
The policy was introduced in 1993 by then US President Bill Clinton.
It was a compromise following controversy when Mr Clinton tried to lift the long-standing ban on homosexuals serving in the military.
The GAO study found that, since that time, the US military had lost 9,488 service men and women because of the policy.
Of those, 757 were in critical occupations such as interpreters and intelligence analysts.
Some 322 had proficiency in strategically important languages that the Pentagon has said are in short supply, the GAO concluded.
'Bin policy' call
The GAO said it was not possible to estimate the full costs of the Pentagon's policy on homosexuals.
But it said it cost around $190 million to recruit and train replacement personnel.
Democrats representative Martin Meehan said he would introduce a bill next week to repeal the policy, Reuters news agency reported.
"It is more apparent than ever before that, as we conduct a global war on terror and face tremendous personnel shortages, that the 'don't ask, don't tell' law is undermining our military readiness," he was quoted as saying.
Responding to the GAO report, the Pentagon said that of all the military personnel discharged for various reasons between 1994-2003, just 0.37% was because of homosexual conduct.
Under the "don't ask, don't tell" policy, the US military does not ask about, and service members do not reveal their, sexual orientation.