The filming of a new Tom Cruise blockbuster at a UK studio will create 500 jobs, Chancellor George Osborne said as he appealed to technology businesses to invest in the UK.
Science fiction thriller All You Need Is Kill, which also stars English actor Emily Blunt, is to be made at Warner Brothers' £100 million studios at Leavesden near Watford.
Mr Osborne was speaking at the latest in a series of business summits being held in London to capitalise on the Olympics by attracting international investment.
He announced a trio of investments in east London's Tech City technology hub by Vodafone, Barclays and Tokyo-based mobile social gaming company GREE Inc.
"Taken together, these major investments represent a triple whammy for Tech City. Coming so quickly after the announcements from Facebook and Amazon, British technology has hit a purple patch.
"You will not find a country anywhere in the world that is more open to technology, more open to investment and more open for business. We're putting in place the right vision and the right policies to help your company succeed right here in the UK.
"That's why the world's leading technology companies are beating a path to our shores. And that's why we will continue to do everything we can to help technology investors and entrepreneurs invest, innovate and succeed in the UK."
Mr Osborne said the Government was "leading the world" in supporting technology companies and claimed ministers were pulling out all the stops to ensure the globe's top technology investors had everything they need to succeed in Britain.
The Chancellor said the Government was making "bold changes" to the tax system, pointing to the 5p cut in the top rate of income tax from 50p to 45p announced in March's Budget. He added: "We have introduced the most generous early-stage investment tax breaks in any country in the world."
London mayor Boris Johnson said: "It's fantastic that more and more companies are taking advantage of the enormous benefits of doing business in London, and I am delighted to welcome these new additions to Tech City."