The duke arrived in the UK on Monday for a four-day visit focused solely on his charities.
He was due to attend an engagement for supporters of the Invictus Games at 6pm, leaving only a very small window to see his father, and is set to fly back to California on Thursday.
Since his flying visit to the UK in February last year, Harry has made multiple visits to the UK but has not been granted another audience with the King, despite requests.
However, there has been a recent thawing in relations between the two sides, with senior aides for both the duke and the King meeting in August.
Crucially, the duke’s High Court claim over his security, which pitted him directly against the Home Office, ended in May when he lost his appeal, drawing a line under the spectacle.
The lengthy legal row caused huge concern at Buckingham Palace, not least after the duke made clear he believed the King could intervene on his behalf to help broker a suitable arrangement.
The King was said to have been so worried about being dragged into the case that he was hesitant to engage with his younger son in case his words were repeated in public, placing him in legal jeopardy.
The duke, dressed smartly in a dark suit and tie, was photographed seated in the back of his vehicle as he arrived at his father’s London residence.
Both Buckingham Palace and Sussex aides have taken a vow of silence over the high-stakes meeting, both sides recognising that trust is critical if relations are to be repaired.
The duke, who stepped down from the working monarchy in 2020, levelled a barrage of accusations at the King, the Queen and the Prince and Princess of Wales in his Oprah interview, Netflix documentary, interviews and his autobiography Spare since moving to the US.
He remains estranged from his brother, Prince William, who has been busying himself with a flurry of engagements this week and was away in Cardiff on Wednesday, visiting a new mental health hub on World Suicide Prevention Day.
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