It was thought that William, 41, could have remained away from public duties for longer as his wife, Kate, is in the early days of recovery after major abdominal surgery.
He stepped back temporarily from his royal role three weeks ago – but the announcement of his return was likely made to signal stability within the monarchy despite the health issues they’re battling.
The Princess of Wales is expected to be out of action until after Easter, and it’s not yet known when the king will return to full public duties.
However ‘workaholic’ Charles is set to keep on working behind the scenes, dealing with his famous red boxes and holding his weekly audience with prime minister Rishi Sunak and Privy Council meetings, which can be done remotely.
There are five ‘counsellors of state’ who can step in to carry out royal duties if Charles is unable to fulfil his role – William being one of them – but it is hoped their intervention won’t be needed.
The king and queen were expected to visit Canada in May, and Australia, New Zealand and Samoa for the Commonwealth Heads of Government Meeting (CHOGM) in October.
But Charles’ illness raises the prospect that William may have to deputise for the King, who is head of the Commonwealth, at CHOGM, just like Charles did for the late Queen Elizabeth in the past.
Other trips could be postponed depending on how the king’s health progresses.
Forthcoming events that could see William playing a key role include the Commonwealth Day service at Westminster Abbey at the start of March and the 80th anniversary of D-Day in June.
William will carry out an investiture at Windsor Castle on Wednesday – which is one of his own regular duties – and also attend the London Air Ambulance annual fundraising evening gala in central London in his role as patron of the charity.
Charles called both his sons to inform them of his condition ahead of the public announcement, with the Duke of Sussex preparing to fly to the UK to be with his father despite their troubled relationship.
William, who is in regular contact with the king, is said to have grown closer to Charles in the wake of Harry’s controversial interviews, documentary and memoir, which saw him launch a flurry of allegations at his family.
It is not yet known whether William will meet his brother during his trip to London, with their long-running rift ongoing.
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