Concerns raised around the Queen's mental capacity have been brushed off by a royal expert.
Questions have been asked about the monarch's ability to continue in her role since it emerged last autumn that she has been dealing with mobility issues.
Former Ukip leader Nigel Farage has even said that the Queen's son Prince Charles is "effectively becoming Prince Regent", meaning he can rule on behalf of the monarch.
But royal commentator Richard Fitzwilliams has dismissed the idea as nothing more than "gossip".
The Queen has been seen in recent months using a walking stick and a number of her engagements, such as some during the Platinum Jubilee in June, have been cancelled or shortened.
Charles, meanwhile, has stepped in for his mother at high-profile events such as the state opening of Parliament in May when he and Prince William carried out responsibilities normally handled by the Queen.
The speculation about whether she is capable of fulfilling her duties as head of state have intensified recently after the Queen's traditional welcome to Balmoral Castle was altered.
She normally inspects a military unit upon her arrival at the gates of her Scottish estate but amendments have been made to the protocol this year for the 96-year-old's "comfort" as she starts her annual summer break north of the border.
The tweaks were announced this week as Buckingham Palace confirmed that the event to mark the Queen's stay will now be conducted privately.
A source told Sky News: “This is a change in line with events being adapted for Her Majesty's comfort.”
Speaking to Fox Business, Mr Farage described the opening of Parliament earlier this year as "a really sad moment".
“It looks as though Prince Charles is becoming Prince Regent which means he will deputise for the Queen on big state occasions, on big international visits with US Presidents or whatever it may be,” he said.
However, in an interview with The Express, Mr Fitzwilliams said: "That is gossip. A Regent is if the Queen was incapacitated, that is the period that you have a Regency.
“You saw that with George III, as George VI was made Regent."
He went on: “The Queen is mentally totally alert and carrying out duties, albeit changed duties.
“I don’t see this as a possibility. We will have to see, of course, what is going to happen in the future.”
Mr Fitzwilliams also pointed out that it was significant that the Queen's throne remained empty in the House of Lords as Charles opened Parliament.
He said: “When Charles opened Parliament, you saw that there was a crown, and he was not on the throne.
“He was on the Council throne, so there is no possibility of that at the moment.”
