The Mayor's Senior Advisor for Volunteering, Charities and Sponsorship, Veronica Wadley, said:
"2012 has been an extraordinary year for London and the achievement of hosting the Games has shown what a terrific welcome we can give visitors. With the help of the Team London Ambassadors and other volunteering programmes, we want to build on the city's reputation for being able to deliver the most fantastic place in the world to visit."
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May Brown appealed to immigration officials to allow her sister Martha entry to the UK from Nigeria.