The 22-year-old, who is currently on loan from Spurs at Sunderland, has claimed that he was the subject of monkey chants from Serbian supporters during the Three Lions' 1-0 win over Serbia in their Euro 2013 qualifier.
"It's extremely difficult for Danny," said Villas-Boas. "He was disappointed by that happening, by the situation which he had to live with, the atmosphere he was confronted with.
"I told Daniel I support him completely in this situation. He felt abused and this is obviously a serious matter which at the moment is in the hands of both FAs."
Meanwhile, Spurs are preparing to take on Chelsea at White Hart Lane this Saturday.