David Duchovny has not had an affair with his tennis instructor, his lawyer has stressed.
The X Files actor and his wife Tea Leoni announced last week that they had been separated for a number of months and it had been rumoured that their separation was caused by an affair between Duchovny and his tennis instructor Edit Pakay.
The Mail on Sunday newspaper claimed at the weekend that the 48-year-old actor and Ms Pakay had been involved in a "physical" relationship for at least six months.
But speaking to People magazine, Duchovny's lawyer Larry Stein rubbished the reports.
"The stories about an alleged affair between David Duchovny and his tennis instructor, Edit Pakay, are completely false," he said.
"Ms Pakay denied the rumours to me in person last Friday, saying they are just friends, and in addition, said in writing that such stories are 'lies and deceit."
Duchovny, who currently plays a womaniser in the TV series Californication, had been married since 1997 to Bad Boys actress Leoni, with whom he has a nine-year-old, Madelaine West, and a six-year-old son, Kyd.
It was confirmed last week that the couple have been "separated for several months".
Duchovny voluntarily entered a facility for the treatment of sex addiction in late August and checked out in October, having "successfully completed his treatment".