The Duke of Sussex's security is under scrutiny during his UK tour.
In May, Prince Harry lost a legal case to have his police protection resumed during his UK tour.
In an interview following the decision, he stated that it was unsafe to bring his family back to his country of birth because he could not guarantee their safety.
It is understood that a Home Office review will now examine whether he should automatically receive full police protection during his UK tour, even though he is no longer a working member of the royal family.
According to The Sun newspaper, the process of re-assessing the Duke's threat level is already underway, and a decision is expected next month.
King Charles has previously met the Duke and Duchess of Sussex's children only once.
He last saw his grandchildren, Archie and Lilibet, during the late Queen's Platinum Jubilee celebrations in 2022.
Prince Harry's security was reduced in 2020 after he stepped down from frontline royal duties and moved to the US with the Duchess of Sussex.
In his legal challenge earlier this year, he challenged the decision-making process of the Protection of Royalty and Public Figures (REWEC), a committee that authorizes the security of senior royals on behalf of the Home Office.
REWEC concluded that because Prince Harry was rarely visiting the UK, his security needs would be assessed on a case-by-case basis.
But in doing so, the Duke's legal team argued that REWEC had not properly reassessed the threats he faced when considering his situation in 2020.
His lawyers had argued that he had been "treated poorly," but the court's decision held that there was nothing illegal in the way the decision was made.
A senior judge ruled that Prince Harry's "complaints" about how the decision to change his security was made could not be the basis for a successful appeal.
The decision meant the Duke's security remained outside the automatic, high-level protection provided to senior royals.
He also said that any hope for him and his family to return to the UK was "impossible" given the Court of Appeal's decision, adding: "I cannot see a world in which I would bring my wife and children back to the UK at this time."
At the time, Buckingham Palace said: "All of these matters have been examined repeatedly and carefully by the Court, and each time the same result has been reached."
A government spokesperson said: "The UK Government's protective security system is robust and appropriate.
"It has long been our policy not to disclose details of these arrangements, as doing so could compromise their integrity and impact public safety."