Queen Elizabeth II was among the high-profile figures who honored those who died, as she visited the Scottish city of Glasgow with her husband, Prince Philip.
Meanwhile, the British Embassy in Tunisia
staged a memorial ceremony on the beach adjoining the Hotel Riu Imperial Marhaba, where mourners have left piles of flowers in tribute to those gunned down as they enjoyed a Mediterranean vacation.
The British ambassador and Tunisian Prime Minister Habib Essid laid a wreath at the scene, while dozens of tourists and Tunisians gathered on the sand, some under palm-thatched sunshades and others standing silently in the surf.
Armed security officers stood by, a visible symbol of Tunisia's effort to reassure visitors that they will be kept safe.
Matches at Britain's iconic tennis tournament, Wimbledon, were scheduled to start later
than usual to allow spectators and players to join the somber moment of remembrance at noon local time (7 a.m. ET.)
Flags flew at half-staff at Buckingham Palace and Downing Street, as well as at public buildings around the country.
The minute's silence was also marked at British embassies worldwide.
Britain suffered the heaviest loss in last week's attack on the hotel in the town of Sousse, which claimed 38 lives in total.
The UK military is bringing the bodies home over several days
. A third plane carrying victims' coffins is due to land at the RAF Brize Norton airbase Friday, with the fourth and final flight due Saturday.
The eight victims being brought home Friday have been named as: Christopher and Sharon Bell, Scott Chalkley, Sue Davey, Angie and Ray Fisher, Eileen Swannack, and John Welch.
The gun rampage is the most significant attack against British citizens since the London transport bombings 10 years ago
Tunisia's Ministry of Interior said Thursday that eight suspects, including a woman, had been arrested in connection with the terror attack.
Kamel Jendoubi, minister for civil society, said all the victims have been identified and all those injured have left hospitals.
Tunisian authorities have named Saif Al-Deen Al Rezgui, who was shot dead nearby, as the sole gunman in the attack.
They say Al Rezgui, 24, trained with the people who carried out the attack on the Bardo Museum in Tunis
In an online audio statement, ISIS
, which has said it's behind the beach resort attack, claimed responsibility for the Bardo Museum attack. CNN could not independently verify the legitimacy of the audio claim.
The Interior Ministry has said it is seeking suspects Rafeeq al-Tayary, 28, and Mohammed bin Abdullah bin Mohsen al-Shirady, a 23-year-old student, in connection with last week's attack.
Another suspect being sought in the Sousse and Bardo Museum attacks is Shams Eddin Sindy, according to the Interior Ministry's webpage.