In every corner of the land, Britons of all ages stood still and bowed their heads

The tall, upright elderly man with brushed-back silver hair positioned himself behind the wall above Trafalgar Square. He waited patiently at the old centre of Empire, watching the hands of Big Ben draw towards each other.

The tall, upright elderly man with brushed-back silver hair positioned himself behind the wall above Trafalgar Square. He waited patiently at the old centre of Empire, watching the hands of Big Ben draw towards each other.

As its chimes and those of St Martin-in-the-Fields just behind him and of all the other clocks in London and around Britain began to strike 12, and the three minutes of silence began, he rested his gloved hands on the parapet and bowed his head in respect to the victims of the tsunami. All around him and across the country, millions of people did the same.

Around the square, the normal roar of traffic became muted; it did not stop completely, but many buses and vehicles pulled over. As the first minute of the silence ticked by, a large number of people continued to go about their business, until it dawned on them why everyone else was still. And then, they too stopped and bowed their heads. But although the Union Flags on Buckingham Palace and public buildings everywhere were being flown at half-mast, this was not simply a British or EU-inspired gesture. It was truly a global moment of remembrance. To one side of the square, the flag of South Africa was at half-mast above its High Commission. Opposite the flags above the Canadian, New Zealand and Ugandan High Commissions and the Malaysian Tourist Office also fluttered low.

Just under the wall where the old man stood, Piihomia Lee, 30, on holiday from Hawaii, had come to observe the silence. She said: "I came here because it seemed like a good place for quite reflection with others. It is important that we all do this.''

Around the country, the silence was marked in high streets, shopping centres, on trains and in railway stations, airports, public buildings and offices and factories of all kinds. It was observed by broadcasters, by the Royal Family and by the Prime Minister. At the stroke of noon, the London Stock Exchange and Lloyd's of London halted trading while the London Eye stopped turning for three minutes.

Back in Trafalgar Square, the silence ended, the crowds stirred and the traffic roared back up to full volume. The silver-haired man straightened and walked off, blinking away tears.