Amritsar: Seeking recognition of Sikhs's contribution in the World War, UK-based Sikh Federation has demanded a monument for them in central London. Sikh Federation chief Bhai Amrik Singh told Times of India on Wednesday that he had made it clear to the UK government that there should be a permanent monument in central London in the next four years to recognize the Sikh contribution and show turban-wearing Sikhs were the 'lions of the great war'. He said when Britain declared war on Germany on August 4, 1914, it had only 150,000 combat-ready troops. It could commit only a little over 80,000 troops to the Western Front in the initial days. The only professional standing army that Britain could bank upon in that crisis was the Indian army with its many turban wearing Sikh soldiers. These troops became the first fighting non-white colonial soldiers in Europe ever, he said. He said Sikh households across the UK on Tuesday took part in the Lights Out project to mark the exact time when Britain entered the first World War. "Prayers were also offered at 250 Gurdwaras to remember those who lost their lives," he said.