The firm shifted its tax base to Ireland over 18 months ago in protest at what it estimated as tens of millions of pounds of additional taxes imposed by the UK government.
Sorrell told Sky News: “On the assumption that the appropriate guarantees could be given, then yes we would return. One of the complications is that any future government could then change that legislation. We will have to see what the result is.”
The opinions of Britain’s business leaders have become a key factor in the build-up to the general election on 6 May as the main parties try to persuade the electorate they have the best ideas to help the economy grow.
The Tories claimed this week they would reform Britain’s corporate tax system as part of a drive to prevent companies from moving offshore.
Also, chemicals group Ineos yesterday confirmed it will move its base to Switzerland to cut its tax bill.