Jeremy Corbyn will “embarrass” the Queen if he fails to kneel when he is made a privy councillor next month, according to members of the centuries-old body.
The Labour leader refused to confirm whether he will kneel in front of the Queen when he becomes a member of the Privy Council which was founded in 1659 by Charles II.
Mr Corbyn is expected to be sworn in to the council next month when the Queen returns from her annual break in Scotland.
As part of the Privy Council ceremony, politicians kneel on a small foot stool before the Queen and brush her bare hand with their lips.
When asked if Mr Corbyn would kneel in the ceremony in a BBC interview this week, he said: “’I didn’t know that was involved actually. So we’ll have to find out about it, OK?”
Owen Paterson, a former Tory Cabinet minister who has been a member since 2010, said that Mr Corbyn had “to grow up” and accept that he would have to kneel in front of the Monarch.
He said: “He is being completely beyond childish – you grew out of this sort of nonsense in your first year at university.
“The whole thing is just ridiculous – he should grow up or go back to the back benches and play around like some sort of bearded activist.”
Keith Simpson, a Conservative MP who was made a member of the Council earlier this year, said: “It would probably embarrass the Queen – she tries to fit in with everyone and meets a wide variety of people. It is impolite, it is bad manners frankly.
“You get the feeling that he is wanting to wear a hair shirt on this – and I suspect it is a toe curler for many Labour MPs.
“It was never a problem for men of impeccable socialist credentials like Clem Attlee and Harold Wilson.”
Elfyn Llwyd, a former Plaid Cymru MP and a member since 2011, said Mr Corbyn would be ill advised not to kneel in front of the Queen as it might mean that he cannot join the Council.
He said: “I would strongly suggest he goes through with it.”