Policymakers in the US are awaiting the results of the referendum vote nervously with the Obama administration reaffirming its hope that Britain remains a member of the EU.

Republicans including Ted Cruz, however, have warned the President not to meddle in referendum, saying they will back Britain irrespective of the result.

At the White House press briefing Josh Earnest, President Barack Obama’s spokesman confirmed that the administration felt the UK would be stronger within the EU.

“But we'll have to see what the outcome is, here. We've been very clear about the president's view that the United States benefits from having UK as a member of a strong E.U,” Mr Earnest said.

“But ultimately, it's the British people who should decide for themselves. They're a sovereign country. They're a country with whom we have a special relationship. And the British people are certainly entitled to make these kinds of decisions for themselves and for their country.”