MPs have concluded more than 18 hours of tributes to the Queen by expressing their loyalty and support to the King.

Commons Speaker Sir Lindsay Hoyle said 321 MPs spoke during the special two-day sitting to share their memories of Elizabeth, who died aged 96, and hail her impact on the country and beyond during her 70 years on the throne.

The second day of tributes ran for more than seven hours and was a rare Saturday sitting, only the second since 1982.

They also approved a humble address to King Charles III in which they expressed the “deep sympathy” felt by the Commons following the Queen’s death, adding: “And to express to His Majesty our loyalty to him and our conviction that he will strive to uphold the liberties and to promote the happiness of the people in all his realms now and in the years to come.”

Adam Afriyie, the Conservative MP for Windsor, was the final backbencher to contribute to the session and he said “there was no escape” from bumping into the “omnipresent” Queen if you lived in the Berkshire town.

Commons Leader Penny Mordaunt, closing the tributes, added: “Our great Queen has entrusted us all with a living legacy of triumph over tribulation, of cheerfulness over challenge, of dedication and determination.

“She has left us, her values remain with us, her example compels us to continued fidelity to our King and our country. God save the King.”

Earlier in the day, Prime Minister Liz Truss and other party leaders took the oath of allegiance to the King.

A select group of senior MPs were given the chance to formally pledge their loyalty to Charles at the Commons despatch box ahead of the second day of tributes to the Queen.

Sir Lindsay explained: “Following the meeting of the Accession Council and the Principal Proclamation earlier today, I’ll first take the oath to His Majesty.

“Time constraints mean a small number of honourable members are able to take the oath and make the affirmation today.”

He added: “There will be further opportunities for all honourable members to take the oath or make the affirmation following her late majesty’s funeral.

“There is no procedural requirement to do so.”

MPs are sworn in after each general election so they can take their seat, speak in debates, vote and receive a salary.

The wording of the oath means MPs have already pledged their allegiance to the heirs and successors of the Queen, meaning they do not have to do it again at this point.

Sir Lindsay was the first MP to swear in followed by Father of the House Sir Peter Bottomley.

Mother of the House Harriet Harman was next in line before Ms Truss stepped forward.

She said: “I swear by almighty God that I will be faithful and bear true allegiance to His Majesty King Charles, his heirs and successors, according to law, so help me God.”

Ms Mordaunt and Labour leader Sir Keir Starmer were among those MPs who opted to affirm.

SNP Westminster leader Ian Blackford, Liberal Democrat leader Sir Ed Davey, the DUP’s Sir Jeffrey Donaldson and Plaid Cymru Westminster leader Liz Saville Roberts were involved in the ceremony.

Ms Saville Roberts took the oath in both English and Welsh.

Conservative former prime minister Theresa May was also among the 30 MPs to take part in the 10-minute ceremony.

Opening the tributes on the second day, Deputy Prime Minister and Health Secretary Therese Coffey praised the “constancy” the Queen gave the nation through decades.

Ms Coffey said wherever she travelled around the world during her time as an environment minister the Queen was “held in the highest regards and there were always representations made for her”.

Conservative former Cabinet minister Greg Clark said the Queen’s “dazzling 1,000-watt smile” for visitors showed she recognised everyone who met her would treasure the moment forever.

Mr Clark said he would “always be grateful” to former prime minister Boris Johnson for reappointing him to the Cabinet over the summer, noting: “I was able to swear the oath of office to Her Majesty in person herself on July 8 at Windsor Castle.

“And when I shook Her Majesty’s hand I was greeted with the most dazzling 1,000-watt smile, sparkly eyes that suggested she was absolutely thrilled to see me.

“Now, I strongly suspect that Her Majesty’s demeanour did not reflect the fulfilment of a three-year hope that the prime minister would restore me to office.

“Instead it showed that at the age of 96, on a hot summer’s afternoon, Her Majesty still recognised that for everyone she met it was a moment that they would treasure forever.”