For years, Gordon Brown was told that companies would leave the UK in protest at his tax policies when he was chancellor. Alistair Darling, his unfortunate successor, is now reaping the whirlwind.

The move will be worrying not just politicians but the profession as a whole. If headquarters depart, so do support services and the jobs associated with them.

Although Shire Pharmaceuticals stressed its UK head office would stay put with its board whisked up to Dublin for important decisions, it doesn’t bode well for the future of head offices in this country.

Chris Morgan, international tax head of KPMG, said: ‘Over time it is inevitable that these migrations will lead to loss of jobs. The problem with multi-nationals operating globally is they will not choose to do their business in a place which is more expensive than another one. When this happens you start to erode the reason for them to have a base in the UK.’

Bill Dodwell, head of tax policy at Deloitte, points to the fact that companies are no longer choosing the UK as their base when they want to expand internationally.

‘We haven’t seen anyone come to the UK for some time. With global mergers the parent company of choice used to be the UK but not anymore,’ he adds.

But tax campaigner Richard Murphy says you can’t blame the government for tightening up the regime on foreign profits. He believes companies which move to Ireland will be under intense HMRC scrutiny over transfer pricing.

‘In practice it will mean we will have to co-operate more fully with the EU,’ he says.

This could lead to the UK being more receptive to the EU’s common consolidated corporate tax base proposals, where total profits would be appropriated to different member states according to the level of work force, assets and capital there.

‘This is one way of the government addressing the problem of corporate mobility. It’s a potential solution but the political ramifications are huge,’ says Morgan.