Prime Minister Boris Johnson outlined his vision for Britain at the centre of a new global free trade area when it leaves the European Union on January 31 in a pitch to African leaders at an investment summit in London. Mr Johnson declared that London was the “ultimate one stop-shop for the ambitious growing international economy” as he sought to differentiate the UK from the “many suitors” seeking to tap into burgeoning African economies. He declared a “new start” in business partnerships with African nations after he won a large majority at national elections in December which cleared the way Britain to Brexit at the end of the month. The conference organisers said it was the largest event of its kind involving governments and businesses from the UK and Africa and seeks to tap into the growth potential in Africa. However, the summit was held as the BBC and Guardian newspaper published details of leaked documents that alleged that Africa’s richest woman, Isabel dos Santos the daughter of Angola’s former president, amassed her fortune by exploiting the country. The prize for investors is becoming part of the world’s fastest growing and most youthful economies. Africa has the world’s youngest populations and by 2030, 42 per cent of the world’s youth will be from the continent, according to officials. “This is a competitive world, you have many suitors,” Mr Johnson told an audience of African business and political leaders in east London, citing China, Germany, France and Russia as rivals in efforts for joint African investment opportunities. Mr Johnson cited a monorail project in Cairo that will be supplied by UK-made trains as part of efforts to capitalise on links developed through the UK’s colonial past on the continent. The summit – which was expected to be attended by 16 African leaders including President Uhuru Kenyatta and President Abdel Fattah El Sisi – is the UK’s largest effort to date in the year of Brexit as it seeks to expand global trade. Prince Harry was also attending despite the announcement last week that he and his wife Meghan would be stepping back from Royal duties. Mr Johnson said that the UK will on January 31 embark on a “new future as global free trading area” and vowed to intensify and expand existing links with African nations. He raised the issue of immigration after criticisms of industry that Brexit could stifle the flow of talent to the UK. Mr Johnson said that his government would put “people before passports” to attract the most talented people from around the world. “Africa is the future and the UK has a huge and active role to play in that future,” he said. “We will be a partner, your partner, through thick and thin.” Nigeria's President Muhammadu Buhari, who attended the summit, said Brexit offered an opportunity for increased free trade across the Commonwealth -- and said visas were a key issue. "While many in the African diaspora enjoy considerable benefits from life in the West, they do not always feel at the heart of the community," he wrote in The Times newspaper. “A renewed sense that there are ties that bind us … could act as a spur to encourage togetherness and the certainty of belonging.” The summit will include a focus on sustainable trade and clean energy investment opportunities, according to the agenda. The premier said that UK – which has set a target of reaching net zero emissions by 2050 – will no longer support coal-related projects in the continent as part of its environmental ambitions.