UPDATE 1-WPP leaving Britain for Ireland over tax changes

(Refiling to remove extra word in headline) (Updates with company spokesman confirming newspaper report)

LONDON, Sept 28 (Reuters) - WPP (WPP.L), the world's second-biggest advertising and marketing group, plans to move its domicile from Britain to Ireland because of punitive changes to the British tax regime, a spokesman said on Sunday.

The decision to shift the British group's official headquarters offshore is a blow for the government, particularly as WPP Chief Executive Martin Sorrell has acted as an ambassador for British business.

He also played a role in helping win the 2012 Olympics for London.

Earlier this year, drugmaker Shire (SHP.L) and media group United Business Media (UBM.L) also both decided to shift their tax domiciles from Britain to Ireland because of planned tax changes on foreign earnings.

And other big names in British business have warned the new rules could trigger a wider corporate exodus.

WPP, which conducts nearly 90 percent of its business outside Britain, paid 204 million pounds ($375 million) in tax last year and reckons the changes would add tens of millions to its British tax bill.

The spokesman said WPP was likely to issue a stock exchange announcement in this week on its plan to change domicile, which was first reported by the Mail on Sunday newspaper. ($1=.5440 Pound) (Reporting by Ben Hirschler; Editing by Paul Bolding and Maureen Bavdek)