Scores of multi-nationals are set to flock to the UK and set up their global headquarters to take advantage of the country's new tax regime, according to E&Y.

The firm revealed that at least 20 companies are expected to complete in the next 12 - 18 months, generating around £1bn of additional annual tax revenues.

Around another 20 are set to follow suit in the months and years ahead, adding over 2,000 high value jobs in the UK workforce.

John Dixon, Ernst & Young's UK head of tax, said: 'Based on the work we are doing with clients, the UK seems close to achieving its ambitions of becoming one of the most competitive corporate tax regimes in the G20. We know of more than 40 multinational companies that are looking to undertake global and regional headquarter (HQ) relocations into the UK, with 20 expected to complete in the next 12 to 18 months. And the momentum is building.

'These transactions are at an advanced stage and, if they all complete, would generate over £1bn of additional annual tax revenues and over 2,000 high value senior management jobs. And that's a conservative estimate; the employment figure is likely to be even higher, as they will also need teams and support services.'

Dixon said that while the public's attention has largely been focused on global HQ domestications, these are the tip of the iceberg.

'The real transformational change that is taking place is around regional HQ transactions; when a large multinational moves part of its operations to the UK. These transactions are almost invisible to the public eye, but they are where the real energy is; they can be transformational to the UK economy in a very material way.'

In August WPP, the world's largest advertising company, said it would be heading back to the UK following its self-imposed low-tax exodus to Ireland, where corporation tax is just 12.5%.

Dixon said tax reform was an 'incredibly powerful way of changing global corporate behaviour'.

He continues: 'These transactions are the culmination of a whole package of measures, rather than a single policy. The Controlled Foreign Companies (CFC) reforms; changes to the headline rate of corporation tax; and a patent box regime that encourages intellectual property to stay in the UK, are all starting to have a real impact on the UK's attractiveness as a place to do business. It's sending out a very clear message - Britain is open for business.'

US, European and Asian companies are among those most likely to migrate to the UK, E&Y said.