Brad & Angelina Mum on Relationship
04/27/2005 AT 01:00 PM EDT
But as evidence of a romance mounts, a close source maintains that there was nothing improper going on before Pitt separated from his wife Jennifer Aniston in January.
"He didn't do anything while he was married," the source tells PEOPLE. "He'll go to the grave saying that."
Of the recent intimate Pitt-Jolie African rendezvous, during which the pair shared a romantic $2,000-a-night oceanside villa and journeyed on a half-day safari at the Shimba Hills National Reserve in Kenya, "it is what it is," says the source.
What exactly is "it"? Although the same source says that the stars "are obviously friends," it seems unlikely that "just plain pals" would go to the trouble of meeting in a remote pocket of Kenyan coastline.
On April 19, the sexy stars were photographed strolling on Kenya's Diani Beach with Jolie's 3-year-old son Maddox. Back at the luxury Alfajiri Villas where the trio were staying, "Brad and Angie looked very jovial," says an observer. "They walked together, laughed."
It's especially telling that protective mom Jolie – who has often spoken of her desire to keep the men in her life at a distance from Maddox lest he get attached to one – has clearly given Pitt the green light. Whether sharing downtime on the set of their upcoming film Mr. and Mrs. Smith in L.A. last spring or cavorting in Kenya, Pitt and Maddox have forged an obvious bond. While shooting Smith, "Brad liked to play with (Maddox)," says an on-set source.
With Pitt, 41, continuing his humanitarian work in Africa – and preparing to shoot the drama Babel in Morocco with Cate Blanchett – and Jolie, 29, stateside for this week's appearance on Inside the Actors Studio, the pair are maintaining their public silence for now. All that may change, however, when publicity gears up for the June release of Mr. and Mrs. Smith – and audiences can judge the Pitt-Jolie combustibility for themselves.
"They have amazing chemistry onscreen," says a source who worked with them on Smith. "They are insanely hot people."
For more on Brad and Angelina, pick up the latest issue of PEOPLE, on newsstands Friday.