'Love Story' star Ryan O'Neal, who has four children - Tatum, 48, Griffin, 47, Patrick, 43, and 27-year-old Redmond- from three different relationships, denies he had a "brief romantic relationship" with Jessica Zellers last year which led to her getting pregnant.

A source close to the 71-year-old actor - who has stage four prostate cancer - revealed he has agreed to the test in order to "put this behind him."

In a statement to RadarOnline.com, Jessica's attorneys said: "Last week we sent a request for a voluntary paternity test in the form of a court-admissible cheek swab from Mr. O'Neal.

"He and his lawyers were given the name and address of the medical clinic (which took samples from the mother and child), and its hours of operation.  All Mr. O'Neal has to do is go to the correct facility in the West Los Angeles area and the whole process should take 5-10 minutes. This is a very simple and minimally invasive procedure. The qualified medical and laboratory facilities are ready, willing, and able to take the samples from Mr. O'Neal. The cheek swab would clearly settle the issue of Mr. O'Neal's paternity once and for all."

Ryan's representatives have previously said: "This woman's claim is ridiculous and false. She has been harassing and stalking Ryan. He never had a personal relationship with her. This will be the first time a woman got pregnant without having sex or in-vitro."