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Labour leader Jeremy Corbyn will join the Privy Council despite missing its first meeting since his appointment.

It would have been the first chance for the Labour leader, a life-long republican, to be sworn in to the historic group which advises monarchs.

A spokesman for Mr Corbyn said he was unable to attend due to "other commitments".

Labour said it was not a snub and pointed out David Cameron took three months to be sworn in to the council.

Conservative MP Alan Duncan said Mr Corbyn had to decide whether he was a serious political figure.

Opposition leaders can receive briefings from the security services through their membership of the group.

What is the Privy Council?

Media playback is unsupported on your device Media caption BBC Parliament's Daniel Brittain explains who is on the Privy Council, its powers, and whether it is a secret and exclusive as some suggest

The Privy Council dates from the court of the Norman kings

There were separate Privy Councils in England and Scotland prior to the 1707 Act of Union

It convenes, on average, about once a month - and has met six times so far this year

The quorum required for each meeting, with a few exceptions, is three plus the Lord President (currently Chris Grayling)

The Privy Council's role is to advise the monarch of the day in carrying out their duties, such as the exercise of prerogative powers and other functions assigned to them by Acts of Parliament.

Much of its business is rather routine and is concerned with obtaining the monarch's formal approval to orders which have already been discussed and approved by ministers or for the arranging for the issuing of royal proclamations. Queen Anne was the last monarch to refuse an order.

Read a full guide to the Privy Council.

Last month Mr Corbyn refused to say whether he would kneel to the Queen as part of the traditional swearing-in ceremony.

His spokesman said the Labour leader could not make Thursday evening's meeting because of prior commitments and had sent his apologies.

Mr Corbyn's team has not said what the engagement preventing his attendance, although it is understood he may be travelling to a fundraising event tomorrow in Scotland.

"Although Jeremy was unavailable for today's meeting, he has confirmed he will be joining the Privy Council.

"As the prime minister and others did, it is far from unusual to miss the first meeting due to other commitments," said the spokesman.

Media playback is unsupported on your device Media caption Jeremy Corbyn on kneeling to the Queen: "I didn't know that was involved"

The council has about 600 members - although only a handful usually attend the monthly meetings.

Prime Minister David Cameron was sworn in as a Privy Counsellor in March 2006, three months after he became leader of the Conservatives.

Image copyright Privy Council

Analysis: By political correspondent Iain Watson

Jeremy Corbyn's team say he hasn't snubbed the Queen by declining to attend today's meeting of the Privy Council. They say he simply couldn't attend and is awaiting a further invitation. He won't be alone in his non-attendance today.

Usually only about half a dozen ministers attend, and the quorum - which makes the meeting official - is just three. Not every leader of the opposition rushes to be sworn in at the first opportunity - David Cameron took three months to attend.

The ceremony involves a rather elaborate form of lowering yourself to the monarch. It also involves the extensive oath to the Queen, which as a republican, he might find more objectionable. The question is whether Jeremy Corbyn is delaying his swearing in, or trying to avoid it.

Mr Duncan, who is also a Privy Counsellor, said Mr Corbyn seemed to want to put politics above the Queen.

He also added that the new Labour leader needed to decide if he wanted to be a serious political figure or a perpetual rebel.

Shadow Cabinet Office minister, Jon Ashworth told the BBC's Daily Politics that he had been told Jeremy Corbyn "had a private appointment today that he couldn't get out of - but he is going to go and see the Queen".

"He is going to do it and I'm sure he will do it in an appropriate and respectful way and he will get on with it soon."

Meanwhile, the SNP's leader at Westminster Angus Robertson - who has also been appointed to the Privy Council - confirmed he would be attending the meeting on Thursday.

BBC assistant political editor Norman Smith said the MP had said it was essential in order to receive intelligence briefings.