Speakers representing diplomats and foreign government employes who live in Montgomery County and send their children to public schools there asked the county school board last night to revoke its new policy that requires them to pay tuition.

They were supported by State Department officials, who contended that the policy is discriminatory and could lead to reprisals against American diplomats abroad.

"We are being singled out as a community," complained Melinda Sanson-Roman of the Embassy of Nicaragua, who represented Nicaraguan Ambassador Guillermo Sevilla-Sacasa, dean of the diplomatic corps.

Under the new policy, to take effect July 1, tuition will be charged for students whose permanent residence is not in the county, a category that includes holders of 10 different types of visas as well as American citizens whose permanent residence is in other jurisdictions.

Tuition payments would go as high as $2,400 on a sliding scale based on the proportion of state and county taxes paid.

The policy, which is expected to bring in $1 million for the county, was approved last fall at a time when a taxpayers' revolt appeared a prospect.

The only speaker in favor of the policy last night was Karl Schlotterbeck, chairman of the Montgomery County Taxpayers' League, who led the drive to win its adoption. He said that without the policy, taxpayers would have an "unfair and unjust" burden.

Eight other speakers voiced opposition, including Deputy U.S. Chief of Protocol Richard Gookin and State Department legal counsel Horace Shamwell.

The school board did not indicate whether it will revise the policy.