King Charles’s Private Secretary Sir Clive Alderton is despised by the Duke of Sussex.

So deeply does Prince Harry loathe the courtier, who has loyally and tirelessly served his father for more than a decade, that he singled him out for stinging criticism in his tawdry memoir, Spare.

The former diplomat, 59, was held up as an example of everything that was wrong about the British monarchy.

Giving him the nickname ‘the Wasp’, Harry claimed that he was one of three ‘middle-aged white men’ at the heart of the Royal Household ‘who’d managed to consolidate power through a series of bold Machiavellian manoeuvres’.

He said Sir Clive was ‘lanky, charming, arrogant, a ball of jazzy energy’ and described his technique as ‘pretending to be polite, even servile’.

Harry wrote: ‘You’d assert a fact, something seemingly incontrovertible – I believe the sun rises in the mornings – and he’d stammer that perchance you might consider for a moment the possibility that you’d been misinformed: Well, heh-heh, I don’t know about that, Your Royal Highness, you see, it all depends what you mean by mornings, sir.

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‘Because he seemed so weedy, so self-effacing, you might be tempted to push back, insist on your point, and that was when he’d put you on his list. A short time later, without warning, he’d give you such a stab with his out-sized stinger that you’d cry out in confusion. Where the [expletive] did that come from?’

This week, however, Sir Clive found himself in the unusual position of using all his ‘jazzy energy’ and charm to undertake an important mission on behalf of Harry, the man who said publicly that he disliked him and called him a ‘usurper’.

The courtier was asked by the King to help ensure that the Invictus Games, which are due to take place in Birmingham next July, are a success.

The Paralympic-style contest for injured and sick former military personnel, which was created by Harry, threatened to become a shambles after one of the countries taking part, Uganda, said it was pulling out after a letter was sent on behalf of the King clarifying that Harry and his wife Meghan remained non-working royals.

Sir Clive telephoned the country’s military chief, General Muhoozi Kainerugaba, to smooth over relations.

A Ugandan spokesman said ‘Sir Alderton [sic] revealed that King Charles III was moved by General Kainerugaba’s sensitive consideration of the King’s opinion on the upcoming Invictus Games organised by Prince Harry, the Duke of Sussex. Sir Alderton said King Charles III has no problem with Uganda’s participation in the Invictus Games.’

As a result of Sir Clive’s moving pleas to the general, Uganda has returned to the games.

His intervention will have deterred any other countries thinking of following Uganda’s example and withdrawing from the event.

Palace sources say Sir Clive’s involvement demonstrates the King’s support for the Invictus Games and for Birmingham, something that was never in doubt. Invictus was launched by the Royal Foundation of Prince William and Catherine, as well as Harry. At the inaugural games in London in 2014, Charles and Camilla attended the opening ceremony as well as William.

It is, however, not surprising that Ugandan officials were bewildered about the King’s view of Invictus. The fact that Sir Clive had to intervene is a worrying example of the monarch’s confusing response to Harry and Meghan’s return to Britain.

His decision to instruct the Lord Chamberlain, Richard Benyon, to send a letter to government departments and the military on his behalf reiterating the Duke and Duchess of Sussex’s status as non-working royals was meant to clarify their position. In fact, it did the opposite.

If their status was ‘akin to private citizens with commercial and charitable interests’, as the letter suggested, should proud members of the Commonwealth such as Uganda take part in the Invictus Games, of which Harry is patron?

Sir Clive’s intervention is evidence that the King is now dancing to Harry’s tune. Not only is the ‘usurper’ having to work in the duke’s interests, but the Sussexes have managed to achieve what they have long campaigned for: a review of their right to automatic, taxpayer-funded protection.

The fiasco over the education of the children, Prince Archie and Princess Lilibet, who were withdrawn from their school after two days because of security fears, might suggest that the Sussexes’ return has been chaotic. The couple are, however, quietly on their way to achieving what they wanted, thanks to our well-meaning but misguided monarch and his loyal servant Sir Clive.