From the Conservative website:
George Osborne has written to Alistair Darling to urge him to take urgent action to prevent more companies from leaving the UK. Regus, Henderson Group and Charter are all thinking of leaving the UK because of concerns over the tax environment. This follows previous announcements from Shire and United Business Media that they are relocating to Ireland.
George, the Shadow Chancellor, blamed the exodus on the confusion created by Labour's dithering over the business tax regime and the fact that we have some of the highest corporate tax rates in the EU. He called on Darling to adopt our plans to reduce the main rate of corporation tax from 28% to 25% and simply the business tax system: "With companies leaving Britain, weakening an already ailing British economy, I urge you to adopt our proposals in order to restore our competitiveness and help prevent any more companies from deciding to leave the UK."