The ceremony was attended by former prime minister, members of the royal family, current party leaders and many veterans and servicemen and women.
The mother-of-two wore her blonde hair in a half-up, half down style and was joined by the Duke and Duchess of Cambridge, the Queen, the Duke and Duchess of Sussex and Prince Charles and the Duchess of Cornwall.
Kate, William, Harry and Meghan made a rare public outing together after Harry and his wife admitted in a documentary they were struggling with public life and that the brothers were on "different paths".
Boris Johnson, Jo Swinson, Jeremy Corbyn and Ian Blackford also laid wreaths.More news: Alibaba sets eyes on $15bn Hong Kong listing
The Prince of Wales will laid the first wreath on behalf of the Queen.
Elsewhere, silences were observed across the nation to mark Remembrance Sunday as towns and cities carried out their own commemoration.
As the clock hit 11 a.m, those in attendance marked two minutes of silence which ended with the firing of a gun by the King's Troop Royal Horse Artillery.
A representative of Bermuda laid a wreath on behalf of the country at a remembrance ceremony in Britain for the first time today.More news: Stephen Curry Could Miss Entire Remainder Of 19-20 Season
It is also the first time the services have been honoured in this way, coinciding with the 100th anniversary of the Government Communications Headquarters (GCHQ) and the 110th anniversaries of the Security Service (MI5) and Secret Intelligence Service (MI6).
Hundreds of armed forces personnel will also be present at the occasion, alongside Cabinet ministers, religious leaders and representatives of Commonwealth nations.
The Prime Minister and Labour leader were among thousands of people attending the wreath-laying service at Whitehall in central London.
David Burt, the Premier, said: The recognition of the fearless service of Bermudian men and women in the World Wars is a much welcomed addition to the London Service of Remembrance..More news: Kentucky Gov. Matt Bevin demands recanvassing of ballots after results show loss
Bermudas Remembrance Day Parade will take place at the Cenotaph on Front Street from 10.30am tomorrow.
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