Obama 'Brexit' warning takes hold in sterling trade

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U.S. President Obama has ruffled a few feathers among politicians and currency traders with his intervention into Britain's June referendum on its membership of the European Union.

Brexit campaigners were left reeling Friday after the President warned it could take a up to decade for the UK to strike its own trade deal with the U.S.

"Maybe some point down the line there might be a UK/US trade agreement but it's not going to happen anytime soon because our focus is negotiating with the big bloc, the European Union to get a trade agreement done and UK is going to be at the back of the queue," said Obama.

Speaking in Germany Monday, he further backed the European Union, stating that integration across the continent was worth the challenges.

"If a unified peaceful, liberal, pluralistic free market Europe begins to doubt itself, then we can't expect the progress that is taking hold to continue.

"I've come here today to the heart of Europe to say that the United States and the entire world needs a strong and prosperous and democratic and united Europe," he said.

Obama's pro-EU rhetoric triggered action in the currency markets Monday where sterling moved near a ten-week high against the dollar.

Head of global FX strategy at Unicredit, Dr. Vasileios Gkionakis, told CNBC Monday via email that attempts to ride any rally in sterling should be held off until after the June 23 vote.

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However he predicted if Britain chooses to stay in Europe, a rise in the value of sterling could become a big theme for the second half of 2016.

"GBP-USD is significantly undervalued and if the 'Brexit-hurdle' is cleared then fundamentals should take over pushing sterling higher," he said in an email.

Dr. Gkionakis also expects a sterling rise to gain momentum as traders price an earlier date for interest rate rises from the Bank of England.

Today's move follows sterling gains last week after bookmakers odds swung towards the belief that Britain will vote to stay in Europe come the referendum .

According to bookmaker Betfair the odds on Britain staying in the EU have swung to 75 percent since Barack Obama gave explicit backing to the Remain campaign.

Market research firm, YouGov, says Mr. Obama has an approval rating of 72 percent in Britain.

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