Those who can deputise for the monarch if he is overseas on an official trip or ill as Counsellors of State include the Duke of Sussex, who lives in California after stepping down from royal duties, and the disgraced Duke of York.
The Regency Act of 1937 contains provisions for the counsellors and those who can stand in for the king to also include the queen consort and the four most senior adults in the line of succession — the Prince of Wales, Prince Harry, Prince Andrew and Princess Beatrice.
The Daily Mail and on BBC Online reported that the list of royal family members who can officiate when the king is not available is likely to be increased to include the Princess Royal and the Earl of Wessex.
The subject was raised by Labour Peer Viscount Stansgate on Monday in the House of Lords when he asked the government what plans it had, if any, to amend the Regency Act.
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The Labour Peer asked Lord True, Lord Privy Seal and Leader of the House of Lords: “Does the minister not think it time to approach the king to discuss the potential amendment of this act, and in particular Clause 6, which at the moment defines regents in relation to their line of succession to the crown?
“Otherwise, are the government happy to continue with a situation where the counsels of state and regency powers may be exercised by the Duke of York or the Duke of Sussex, one of whom has left public life and the other of whom has left the country?
“Is it not time for the government to approach the king to see whether a sensible amendment can be made to this act?”
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In reply, Lord True said: “The government will always consider what arrangements are needed to ensure resilience in our constitutional arrangements, and in the past, we have seen that the point of accession has proved a useful opportunity to consider the arrangements in place.”
It is thought any amendment to the Regency Act, to increase the number of counsellors, would be completed later this year before the prospect of the king and queen consort going on overseas tours in 2023, which may coincide with the Prince and Princess of Wales also being out of the country.
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Counsellors of State are authorised to carry out most of the official duties of the sovereign such as attending Privy Council meetings, signing routine documents and receiving the credentials of new ambassadors to the UK.
But certain core constitutional functions cannot be delegated, such as appointing a prime minister or creating peers.