LONDON (REUTERS) - US President Barack Obama implored young British people not to pull back from the world on Saturday (April 23), a day after he warned the country of the risks of voting to leave the European Union in a referendum in June.

"We see new calls for isolationism, for xenophobia," Mr Obama told young people at a "town hall" event in London.

"When I speak to young people, I implore them, and I implore you, to reject those calls to pull back.

"I am here to ask you to reject the notion we are gripped by forces that we cannot control. And I want you to take a longer and more optimistic view of history," he said.

Speaking to over 500 young British people, Mr Obama joked about Britain's colonial past, saying that despite the so-called special relationship between the two countries, the United States had once had quarrels with Britain but then made up.

Mr Obama answered 10 questions but Britain's June 23 referendum on its EU membership was not raised during the question-and-answer session which lasted over an hour.

Mr Obama also said a planned trade deal between the United States and the EU had run up against "parochial interests" of individual countries but would create millions of jobs and billions of dollars of benefits on both sides of the Atlantic.

"People right now are especially suspicious of trade deals because trade deals feel as if they are accelerating some of these globalising trends that have weakened labour unions and allowed for jobs to be shipped to low-wage countries," he said.

"And some of the criticisms in the past of trade deals are legitimate. Some times they have served the interests of large corporations and not necessarily of workers in the countries that participate in them," he said.