Prince Harry warned there is 'no exception for royalty' over his drug use

This has led to right-wing think tank The Heritage Foundation calling for Harry's visa application to be released so the American taxpayer can understand whether the Duke declared his drug use.

US immigration law has harsh penalties for lying to immigration officials, including deportation and being barred from applying for citizenship.

The President of West Coast Trial Lawyers and former federal prosecutor, Neama Rahmani has warned Prince Harry that his royal status will not help him regarding his US visa.

He told Page Six: "An admission of drug use is usually grounds for inadmissibility."

"That means Prince Harry’s visa should have been denied or revoked because he admitted to using cocaine, mushrooms and other drugs."

Rahmani added there is "no exception for royalty or recreational use".

It comes as Mike Howell, director of the Heritage Foundation's Oversight Project submitted a request for Prince Harry's US visa application to be made public.

Howell said: "This request is in the public interest in light of the potential revocation of Prince Harry’s visa for illicit substance use and further questions regarding the Prince’s drug use and whether he was properly vetted before entering the United States".

However, a US State Department spokesman said: "Visa records are confidential under Section 222(f) of the Immigration and Nationality Act (INA); therefore, we cannot discuss the details of individual visa cases".

In January, GB News reported that Prince Harry looked set to keep his US visa despite writing about taking drugs in his memoir - an admission that can often see Britons banned from entering America.

A lawyer at leading firm Laura Devine Immigration told GB News that the admissions will not be enough to affect Prince Harry's eligibility for a US visa.

Head of US immigration Christi Jackson said: "Anything that he has admitted to regarding drug use before the age of 18 should not affect his eligibility for a US visa.

"If he had admitted to drug use when he was over 18, in order for it to lead to visa ineligibility, the admission would have to have been a valid admission which means it cannot just be out in the news or written in their book.

"You have to show that the person has provided the definition and admitted to all essential elements of the crime while under oath. Making a statement in a book is not going to be considered a valid admission."

She continued: "So who you’re admitting it to is what makes all the difference. A legally valid admission must be made under oath and recorded.

"If he had admitted to using drugs over the age of 18, that could have possibly led to visa complications if he had been then questioned by US Customs or Border Patrol."