The firm cut its tactical allocation to U.S. stocks to the lowest in three years at "neutral" from "overweight" while initiating an "underweight" on UK stocks.

It remains overweight euro zone shares, citing a combination of quantitative easing, accelerating economic growth, and strong corporate earnings.

"For the first time in years, the U.S. does not have the most attractive profit outlook compared to other regions, particularly the Eurozone," Mark Haefele, global CIO at UBS Wealth Management, said.

"In the UK, earnings dynamics are weaker than in other countries, and the defensive nature of the market means it is less well placed to benefit from an upswing in global markets."

(Reporting By Francesco Canepa; Editing by Lionel Laurent)