The former president, 77, spoke with TV presenter Nigel Farage on GB News, where he suggested the royal would not get 'special privileges' if he lied about his drug use.
Harry, who has lived in the US since 2020, lives in a nine-bedroom Montecito mansion with his wife Meghan Markle and their two children Archie and Lilibet.
In the prince's autobiography 'Spare' he revealed he previously took drugs, which under US law would normally be grounds for a visa application to be rejected.
In the book he admitted to using to cocaine, cannabis and psychedelic mushrooms.