Tobias -- in his former position as ambassador for the President's Emergency Fund for AIDS Relief -- was known for advocating sexual abstinence over condom use. More recently, he served as director of the U.S. Agency for International Development.
Tobias told ABC News Thursday he had been a customer of Pamela Martin and Associates, an escort service, although he said he received massages, not sex. His cell phone number was given the network by Judith Palfrey, nicknamed the "DC Madam," who faces federal charges for allegedly promoting prostitution.
"I'm sure as heck not going to be going to federal prison for one day, let alone, four to eight years, because I'm shy about bringing in the deputy secretary of whatever," Palfrey said in an interview with ABC to be broadcast next week.
She said she plans to call Tobias and other high-level customers to testify at her trial.