Sir Keir Starmer erupted in fury at the Commons Speaker on Wednesday after he was ordered to answer Kemi Badenoch's questions. 

Sir Lindsay Hoyle interrupted the PM to remind him that it was questions to the Prime Minister - rather than the leader of the opposition. 

'Prime Minister, it's Prime Minister's Questions. We've got to concentrate,' he told Sir Keir as the pair clashed.

Following the heated exchange, the PM was seen to approach Sir Lindsay's chair as he left the Chamber to speak to him. 

One MP who witnessed the scene at close quarters said Sir Keir was clearly incensed at the Speaker.

'He was fuming with Lindsay,' they told the Daily Mail.

In a dramatic moment during the exchange, Sir Keir was even seen to whack his fist on the side of Sir Lindsay's chair.  

An MP told the Guido Fawkes website: 'Lindsay stood his ground and was trying to say something back but the PM just walked off.'

It is the third occasion in recent weeks in which Sir Lindsay has had to intervene to remind Sir Keir that he is supposed to be answering questions.

The Speaker later issued a statement saying that he occasionally had to remind PMs of the 'rules of engagement' in the chamber.

He added, pointedly, that the point had been made to No10 officials 'on several occasions recently' following similar interventions on previous weeks. 

A spokesman for the Speaker's Office said: 'The Speaker is not responsible for the questions asked by Members or the answers given by Ministers. 

'Questions to Ministers should relate to matters for which they are officially responsible. Equally, answers should be confined to the points contained in the question. 

'Every so often the Speaker has to remind Prime Ministers - and Ministers - of the rules of engagement in the Chamber.

'The Speaker has made this point to officials at No 10 on several occasions recently as well.'

A Tory source said: 'Starmer is so out of depth he doesn't even know how to answer questions at an event literally titled Prime Minister Questions. 

'The British public deserve so much better than this hapless fool.'

Reform MP Sarah Pochin tweeted: 'I welcome the Speaker holding Keir Starmer to account for failing to answer questions.

'It is not acceptable for the Prime Minister to treat Parliament, PMQs and the public with such contempt. PMQs is not a soapbox for political point scoring, often aimed at Reform, it is a forum for scrutiny.

'He is the Prime Minister, for now. He should start acting like it.' 

Last month, Sir Lindsay told Sir Keir: 'I am sorry I am interrupting you, but unfortunately we have to stick to Prime Minister's questions, not Leader of the Opposition's questions.'

In January, he cut the PM off to tell him: 'We do not ask the Opposition questions. These are questions for the Prime Minister, not the other way around.'

It came as Sir Keir came under fire from all sides over his refusal to reveal Labour's overdue defence spending plans after a top union leader told him to stop dithering and get on with it. 

Unite's Sharon Graham warned the PM that his failure to produce the 10-year defence investment plan (DIP) was 'a threat to national security' because it risked specialist jobs being lost.

The secretary general, who has repeatedly clashed with Sir Keir in recent months, lined up alongside unlikely allies in former Blair/Brown era defence secretaries and Mrs Badenoch to demand action.

But she differed from them in saying that the money required should come from a wealth tax, rather than cuts to welfare.

The PM also again refused to give any timetable for publishing the crucial defence plan today amid bitter Cabinet infighting.

Sir Keir would only say the 10-year investment plan - due to be published last autumn - would be released 'as soon as possible' as he was challenged by Mrs Badenoch at PMQs.

He said he 'respected' ex-Nato chief Lord Robertson - the first latest Labour grandee to demand more funding - but disagreed with his views.

 QUENTIN LETTS: Purple-faced, eyes blazing, Starmer let rip at Sir Lindsay - then whacked his fist on the side of Mr Speaker's throne

Houston, we had a temper tantrum. As Sir Keir Starmer was leaving the Commons chamber at the end of an aimless PMQs, he stopped briefly at the Speaker's Chair and aimed a few words at Sir Lindsay Hoyle. During the session, you see, Speaker Hoyle had been obliged to admonish Sir Keir for once again asking questions about past Tory governments.

Mr Speaker had suggested that Sir Keir try to answer for his own responsibilities rather than deflect blame to others. 'Prime minister, it's prime minister's questions,' said the Speaker.

That moment, at roughly 12.08pm, did not go down well with Sir Keir. He shot a filthy stare at Speaker Hoyle. You could have singed a pink frankfurter with that look of loathing.

Now, some 26 minutes later, we had reached the end of the session and Sir Keir and his aides were heading for the chamber's rear swing-doors. Their route took them straight past Sir Lindsay. Sir Keir snapped.

From my gallery eyrie I had a good view of the moment but was not able to hear exactly what was said. Mind you, one did not need to be a lip reader to discern that the exchange was on the ripe side – the sort of thing a Mediterranean waiter might shout at a mongrel that got under his feet on a busy day at the tapas bar.

'£*$'&+!!!' said Sir Keir, or syllables to that effect. In his first conversational burst there were perhaps six words. They were heavy on the consonants. I could not quite see his tonsil waggling but the prime ministerial face was purple. He was gripping his official folder tightly to his chest. The eyes were blazing.

And normally such a dull little chap! 

Speaker Hoyle is a proud Lancastrian. You do not grow up in Chorley without learning to contest an ambush and, if necessary, to bop your assailant right back on the nose. Sir Lindsay duly returned some verbals to Sir Keir. They were of the 'don't blame me, chum – you were bang out of order' variety. The PM leaned back a bit and blinked a couple of times before pushing his snout forwards once more. He spat out another sentence, lower lip curling. Boy, oh boy. He was furious. This second outburst ended with him whacking his fist on the side of Sir Lindsay's throne.

All this, please note, was happening amid the great whirlpool of Whips and ministers and clerks and backbenchers that eddies round the Speaker's Chair at the end of any PMQs. The Prime Minister was losing his rag with Parliament's impartial referee and he was doing so in full view not only of his troops but also of gawping Tories.

Why in such a steaming bate? Can it be that he knows his premiership is a disaster? Kemi Badenoch had once again got under his pelt by asking a series of serious questions about defence spending, doing so with smoky-voiced composure. Some of Sir Keir's responses were garbled, others were sarcastic. 'I remember it!' he shrieked at one point, referring to Opposition mockery of his non-war policy at an earlier PMQs.

War threatens the globe. Our economy is staggering. Oil supplies are in doubt. Yet we have a prime minister indignant and brittle at some past parliamentary slight.

After Sir Keir hit the arm of Sir Lindsay's chair, the Speaker turned his head away, no longer inclined to spare a petulant prime minister the time of day. With which, ladies and gentlemen, Sir Keir – who only earlier had been presenting himself to the nation as an agent of diplomatic peace and reconciliation – left the chamber at remarkable pace. I have never seen him move faster. To picture the force with which he departed the scene you should picture a water skier being taken by surprise at the start of a ride, when the motorboat has throttled much too suddenly.

Don't let Sir Angry anywhere near a nuclear button, please.