During the battle to host the 2012 Olympic Games, London's amazing diversity was our secret weapon and our winning asset. "Choose London, and you choose the world", we said. We won. Every morning when I drop my kids at school I now see the Olympic Stadium looming up where before there was a wasteland, and I'm incredibly excited – not just about the greatest sporting show on earth, but everything else that comes with it.

However a key criticism leveled at London 2012 has been that local communities, and particularly ethnically diverse communities, have yet to see equal benefit from the games arriving. For example, a few months ago a petition was launched in protest at black-owned business being 'carved out' of Olympics contracts. Perhaps it's no coincidence, then, that the biggest business-focused event happening anywhere in London during the Olympics is powered by London's black community. The African and Caribbean Business Expo, of which I am a patron, shines a light on the UK's diaspora businesses.

We know the Olympics will bring a multi-billion pound boost to the UK economy just when it's really needed. And small businesses from all communities realise they need to stake a claim on these opportunities. Elsewhere, opportunities are hard to come by, particularly for young people facing record levels of unemployment, at a time when the cost of studying becomes prohibitively expensive. The statistics are particularly grim for our black communities, with unemployment rates for African and Caribbean people at more than twice the national average.

But while the UK economy slips back into recession, emerging markets in the Caribbean and Africa are thriving. Did you know that of the 12 fastest growing economies in the world predicted for 2012, half are in Africa? Private sectors across the globe are waking up to the investment and partnership links on offer, and we need to ensure the UK doesn't lag behind. Perhaps the difficulty is in shifting people's perceptions of these regions. Away from the stereotypes of poverty, corruption and violence, there is an alternative picture materialising in Africa. Anyone who does business there will tell you of the vibrant entrepreneurial spirit that goes hand in hand with a growing economic power.

As home to one of the largest African and Caribbean diaspora populations in Europe, the UK is perfectly placed to capitalise on natural links with this side of the world. Ethnicity aside, there are opportunities for all UK businesses with an eye on global expansion as the world descends on London. Don't wait another 50 years for the Olympic torch to come back round. I hope all businesses and communities will benefit from the greatest sporting show on earth - after all, London won't have a better opportunity to stay at home and meet the world.

The African and Caribbean Business Expo takes place from 4-10 August 2012 at the Grosvenor House Hotel on Park Lane.