WASHINGTON - President Barack Obama said on Friday the U.S. relationship with both Britain and the European Union would endure in the wake of British voters' decision to leave the EU."The people of the United Kingdom have spoken, and we respect their decision," Obama said in a statement."The United Kingdom and the European Union will remain indispensable partners of the United States even as they begin negotiating their ongoing relationship," Obama added.Britain's decision at a referendum on Thursday forced the resignation of Prime Minister David Cameron and dealt the biggest blow to the European project of greater unity since World War Two.Obama, during a visit to London in April, had argued passionately against Brexit, or Britain's exit from the EU, in an unusually strong intervention into British politics.He had warned that close NATO ally Britain would be "in the back of the queue" for a trade deal with the United States if it dropped out of the EU, but opinion did not swing in favor of the "Remain" campaign.Thursday's vote result rattled Wall Street and other markets around the world.U.S. presidential candidate Donald Trump on Friday thrust himself into the heart of the Brexit issue, calling the result of the vote a "great thing" and drawing parallels to his own insurgent campaign.In Scotland to reopen a golf resort, he praised Britons who he said "took back control of their country.""People want to take their country back. They want to have independence in a sense. You see it with Europe, all over Europe," Trump, 70, said in Turnberry, Scotland.U.S. Vice President Joe Biden, traveling in Ireland, said the United States would have preferred that Britain had voted to remain in the European Union, but respected the result."I must say we had looked for a different outcome. We would have preferred a different outcome ... but the United States has a long-standing friendship with the United Kingdom and that very special bond will endure," he said in a speech in Dublin.He had traveled to London at the request of Cameron, whom he calls a friend, exhorting Britons to stay in the EU. The unusual intervention was denounced as meddling by those campaigning for the country to leave the EU.Obama has said his involvement was justified because of the two countries' longstanding special relationship. He also had warned that leaving the EU would put Britain at the "back of the queue" for a trade deal with the United States.His former Secretary of State Hillary Clinton, the presumptive Democratic presidential candidate in the Nov. 8 election, had also said she hoped the UK would stay in the EU.In response to Britain's decision to leave, Clinton said the United States must first safeguard against any economic fallout at home at "this time of uncertainty" and underscore its commitment to both Britain and Europe.