Jeremy Corbyn has been sworn in as a member of the Privy Council.
The Labour leader and lifelong republican officially joined the council in front of the Queen at Buckingham Palace.
Tradition usually dictates that new members of the council should kneel on a footstool and kiss the hand of the Queen as part of the ceremony.
And while Labour has said Mr Corbyn followed the "normal processes" during the ceremony the party would not comment further on whether he had knelt or indeed kissed the Queen's hand.
However, speaking to ITV News before the ceremony, Mr Corbyn signalled he would not be kneeling.
"I don't expect to be kneeling at all, no," he said.
"I expect to be nominated to the Privy Council and that's it."
Mr Corbyn turned down the opportunity to attend the council's previous gathering last month, citing prior engagements.
Joining the council requires members to vow to be a "true and faithful Servant unto The Queen's Majesty".
It also involves swearing not to reveal any confidential information.
Every Leader of the Opposition is granted membership to the council so that they can receive secret briefings from the security services.
Members of the council are allowed to use the title of Right Honourable.
The Queen is head of the Privy Council and the body advises her as she carries out duties as head of state.
The council also provides administrative support for the leaders of the Commons and Lords and has responsibility for the affairs of 400 institutions, charities and companies incorporated by royal charter.
It has a judicial role as the court of final appeal for UK overseas territories and crown dependencies and for a number of Commonwealth countries.
The body - the oldest form of legislative assembly still functioning in the UK - dates from the time of the Norman kings when the monarch met in private - hence the description Privy - with a group of trusted counsellors who fulfilled the role the cabinet performs today.
There are around 500 privy counsellors but not all members are required to attend the monthly meetings. It is usually the Queen, the Lord President Chris Grayling and three ministers, plus any who are being sworn in. Discussions are held standing up, ensuring they do not last too long.