Sounding like a jilted lover, Sir Keir Starmer said in a hurt tone that Boris Johnson had not replied to his letter, sent in confidence a fortnight ago.

Anyone who sets out to have a relationship with Johnson ought to know that replying to letters is not his thing. He is the kind of man who reckons it is best not to put anything down on paper.

“I took the trouble to ring him up,” Johnson protested. “He didn’t offer any dissent at that stage.”

Johnson is starting to feel fed up with Starmer. The Leader of the Opposition promised to be constructive, but here he was, trying to make the Prime Minister feel guilty.

In Johnson’s view, this carping has gone on for long enough. Loyal opposition is one thing, but Starmer had strayed into disloyal opposition.

The Prime Minister suggested to the Leader of the Opposition that “he’s on better ground, firmer ground when he stands with the overwhelming majority of the British people”.

Already he had accused Starmer of being “polemical”. Now he was accusing him of being unpatriotic.

If Starmer’s style had been formed at the Oxford Union, he might have retorted that patriotism is the last refuge of the scoundrel and the populist.

But Starmer’s style was formed in a court of law, where as prosecutor he assembled the evidence required for a guilty verdict, and went on doing so for as long as it took.

Johnson could find himself on trial until December 2024, the last moment when a general election will have to be held.

What an intolerable prospect, to have to defend himself week after week against this pettifogging lawyer, who only sent him that confidential letter in order to catch him out. The Prime Minister felt so cross he began jabbing his finger against the Dispatch Box.

Starmer observed in a plonking tone that “the Statistics Authority has had concerns on more than one occasion”.

“I really do not see,” Johnson retorted, “the purpose of these endless attacks on public trust and confidence.”

The attacks were actually on him, but if successful they would undermine public confidence in the Government, so with characteristic ingenuity – his enemies would say with characteristic unscrupulousness – Johnson sought to conflate the two.

Starmer accused him of confusing scrutiny with attacks, called for leadership and consensus, and added that “the scenes yesterday of members queuing to vote were frankly shameful.”

Johnson retorted that “ordinary people are getting used to queuing for long periods of time”. A wounding blow, for it implied that Starmer is not an ordinary person.

But Johnson has no desire to antagonise other MPs, especially on his side of the House, for on them his continuance in office depends, so he added, apropos the queuing, “I apologise to colleagues for the inconvenience,” and said that those who need to be shielded “should be able to vote by proxy”.

Even with only 50 MPs in the Chamber, separated by many yards of black and yellow tape, the House works far better like this than when operating in virtual form.

I count myself lucky to have been among the dozen or so journalists who were able to watch the contest from the press gallery.

Johnson and Starmer are two magnificently incompatible figures, each of whom is brilliant in his own way, and is bound to find the other infuriating.

Today there was no victor in their duel, but already this odd couple have rescued PMQs from the torpor into which it had fallen.