The US has a profound interest in a “strong UK staying in a strong European Combination”, says the US Secretary of State.
John Kerry said various Europeans felt “overwhelmed” by recent challenges but the US was confident Europe make “emerge stronger”.
His comments in Munich come ahead of a crucial Brussels climax, where Prime Minister David Cameron is hoping to secure a apportion on a reformed EU.
An EU-exit group said the US stance on Britain leaving was “for US induces”.
Mr Cameron, who was also in Germany, said changes he was seeking to UK membership would procure Europe “more outward-looking, competitive and dynamic”.
He hopes to secure a carton that he can recommend to the British public, ahead of a referendum on whether the UK should mainstay in or leave the EU.
Mr Kerry, who spoke about the EU while at safety conference in Munich, said Europe was facing a number of challenges classifying the UK’s potential exit.
“Here again however, I want to express the trust of President Obama and all of us in America that, just as it has so many times in the forefront, Europe is going to emerge stronger than ever, provided it deters united and builds common responses to these challenges,” he claimed.
“Now obviously, the United States has a profound interest in your success as we do in a vastly strong United Kingdom staying in a strong EU.”
Guide: All you need to be familiar with about the referendum
Last year, US President Barack Obama predicted the UK must stay in the EU to continue to have influence on the world stage.
A spokesman for Come out for Leave, one of two groups vying to be the official Out cam ign in the EU referendum, told the BBC the British direction was “pulling favours” from world leaders.
“The State De rtment has want thought the UK is better off in for US interests,” he said.
“But this vote is nearby the future of the British people and Britain’s best interests and we’re confident the British child will vote to take that control.”
However, Britain Stronger In Europe – a rank cam igning for Britain to remain in the EU – said Mr Kerry’s comments reinforce how Britain’s “international influence is clearly enhanced by staying in Europe”.
Executive director Last will and testament Straw said: “Being in an alliance with 27 other European democracies fortifies our hand when dealing with threats like terrorism and a resurgent Russia. And additions our clout and credibility in Washington.”
In a speech to house, political and civic leaders in Hamburg, Mr Cameron said he would compete “unequivocally” for the UK to stay in – if the EU agreed to the new terms of membership.
While defending Britain’s propriety to protect its sovereignty, he told his audience – which included German Chancellor Angela Merkel – that Britain was an “extend nation” and he “never wants us to pull up the drawbridge and retreat from the life”.
“So when it comes to the question of Britain’s future in Europe, my aim is clear,” he voted. “I want to keep Britain inside a reformed European Allying.”
Mr Cameron also appealed for Germany’s help in finalising reforms, stressing the territories’ shared interests and values.
Negotiations on the final wording of the deal – which embraces an “emergency brake” on benefit yments to EU migrants and a UK opt-out from “period closer union” – look set to carry on right up to the start of the Brussels climax on 18 February.
Cam igners for an EU exit have said the draft allot, published earlier this month after months of negotiations between UK and EU officials, did not end up close to the changes voters had been promised.
No date has yet been revealed for the referendum although Downing Street is reported to favour staging the survey in June.
Further reading on the UK’s EU referendum
EU renegotiation: Did Cameron get what he lack?
Referendum timeline: What will happen when?
The view from Europe: What’s in it for the others?
Sundry: BBC News EU referendum special