(CNN) -- A videotape on a Russian Web site allegedly showing a State Department employee having sex with a prostitute is a "smear campaign" meant to discredit the man, a State Department spokesman said Thursday. The State Department has said the tape allegedly showing an employee having sex with a prostitute is a fake. The employee, Brendan Kyle Hatcher, denied any encounter with a prostitute to his superiors at the U.S. Embassy in Moscow, another State Department official said. State Department spokesman Ian Kelly said the U.S. ambassador to Russia, John Beyrle, "supports" Hatcher, who remains at his job at the embassy.
@highlight
NEW: Russian officials are being "very cooperative," U.S. official says
@highlight
Russian site allegedly shows State Department employee having sex with prostitute
@highlight
U.S. ambassador says video clips "clearly fabricated"
@highlight
Official: Tape meant to discredit employee working in religious and human rights
"Mr. Hatcher ... enjoys the full confidence of Ambassador Beyrle and fully intends to serve out the rest of his tour in @placeholder," Kelly said at an afternoon briefing at the State Department.