Wikipedia founder Jimmy Wales said: "I think that's one of the biggest dangers is the impact on the start-up ecosystem in Shoreditch. If we want to host the next Facebook we want those young companies 100 per cent focused on making a great product that people enjoy.
"Paying them to deviate from their normal task in order to comply with complex security regulations; it's just going to kill it.
"Certainly we already know that there is a brain drain to Silicon Valley. Loads of young entrepreneurs will go there. The harder we make it for people to do business here the easier we make it for the US to get all our best talent."
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Feeling warm in the sunshine
Speaking after the Westminster attack, Brad Smith exclusively told ITV News that Microsoft will only hand over data when legally compelled.
Kurt Cochran and his wife Melissa had been visiting London from the US to celebrate their 25th wedding anniversary and were due to fly home.