King Charles tried to reach out to his friend Sir Ranulph Fiennes to check on his wellbeing amid worries over his care, according to reports.

reports that the King was said to be “most concerned” about the 82-year-old explorer after Anton Bowring, Sir Ranulph's business partner and long-standing friend, alerted him to his declining health and isolation in February last year.

The King’s equerry, William Thornton, then contacted Mr Bowring to ask how Charles could get in touch with Sir Ranulph and was given a number for his wife, Louise Millington-Cotes.

But, according to , Ms Millington-Cotes did not put the King in contact with her husband.

In the last couple of weeks, friends and family have rallied around Sir Ranulph, who has not been seen in public for two years, amid growing concerns over the conditions of his care.

It comes after a care home owner in Wales, where the explorer had been placed for seven weeks this year, told they had reported several concerns about Sir Ranulph’s wellbeing to the authorities, including the police.

The newspaper claimed to have seen an email sent by a care watchdog that reportedly said Sir Ranulph was being unlawfully kept in care homes and unable to consent to his care or treatment.

Mr Bowring had reached out to the King last February to inform him that Sir Ranulph had been “in a very poor state”.

He told the newspaper that the King’s equerry, Mr Thornton, responded to say “the King was most concerned and would really like to write to Ran, Louise and their daughter Elizabeth to express his concern and see if there was anything he could do to help.

“He asked how he could communicate that to Ran, and asked if I had Louise’s phone number,” Mr Bowring said. “He said ‘I can give her a ring and if it’s a no we can let the matter drop’.”

Sir Ranulph’s stepson, Alexander Millington-Cotes, is calling for an investigation into his whereabouts after being unable to see his stepfather for more than a year.

He claims that police forces, including West Mercia Police and Cheshire Constabulary, have ignored his pleas for help. Both have been contacted byfor comment.

The stepson is urging for action to be taken “swiftly” and has set up a GoFundMe page that has so far raised more than £18,000.

Several British adventurers, including Ben Fogle and Bear Grylls, have also called for an investigation.

Mr Fogle said he was “deeply disturbed” by the reports about Sir Ranulph, writing on social media: “It is time for the Office for the Public Guardian and the police to investigate this case.”

Mr Grylls claimed he and others had been “desperately trying to connect with Ran for a year now to no avail”.

He said: “Ran is a true British icon for so many around the world – a pioneer, a humble warrior and a good friend to so many of us. He never failed to support me when I needed help. Now is our time.”

Buckingham Palace has been approached for comment.