BRASILIA, April 22 (Xinhua) -- Brazil's Federal Police revoked the diplomatic credentials of a U.S. immigration officer based at the U.S. embassy in Brasilia, the agency's director general, Andrei Rodrigues, said Wednesday.

Following Washington's recent expulsion of a Brazilian Federal Police attache, the measure, based on the "principle of reciprocity," stripped the officer of access to the unit where he worked and to certain databases, Rodrigues told the local press.

He added that the officer's credentials will remain revoked until Washington clears up the status of Marcelo Ivo de Carvalho, the Federal Police's envoy in the United States.

The U.S. administration revoked Carvalho's visa on Monday. The State Department's Bureau of Western Hemisphere Affairs accused him of attempting to "game" the immigration system to "circumvent formal extradition requests" and "extend political witch hunts into U.S. territory."

Brazilian President Luiz Inacio Lula da Silva said on Tuesday that the government would take reciprocal measures. ■