British businesses faces a tough choice in this year's general election, the CEO of the world's biggest advertising agency told CNBC Monday.
Voters go the polls on May 7 in an election that many analysts say is too close to call.
"It's a very difficult choice at the election if you're in business," said Martin Sorrell, the CEO of WPP Group.
He said businesses were faced with the choice of a government led by the Conservatives, who lead the current coalition and promise a referendum on Britain's membership of the European Union, and the opposition Labour Party.
"I doubt the Conservatives will be the majority party, but they may be in control of a coalition and you're faced with the uncertainty of an EU referendum. It's either a neutral or negative impact, it's not positive," Sorrell said.
"If you vote Labour, the Labour platform seems to be bashing business, which makes business people a little bit uncomfortable," he added.
Peter Kellner, president of research firm YouGov, told CNBC on Friday that he believed the U.K, was heading for a hung parliament in May – where no one party has an outright majority to form a government.
Earlier on Monday, WPP unveiled its 2014 earnings results which were broadly in line with analyst expectations. The company reported a 3.3 percent rise in sales in 2014 and said it would target sales growth of over 3 percent in 2015.
"The economy is in a much better shape than at the time of the last election. Over the past five years our revenue has grown by over 50 percent to $3.2 billion dollars and the number of people we employ in the U.K. has gone up from about 12,000 to 16,000," Sorrell said.
"So we have done extremely well, we would expect a stutter after the election as the next government has to focus on the (budget) deficit ahead of the next election which may not be another five years go," he added.
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