London ( CNN ) -- American and British leadership of the world remains `` essential to the cause of human dignity , '' President Barack Obama said Wednesday , making a sweeping case for values including freedom and the free market in a speech to a joint session of the British Parliament . `` We must act , and lead , with confidence in our ideals , and an abiding faith in the character of our people , '' Obama said , even while adding they will `` proceed with humility , and the knowledge that we can not dictate outcomes abroad . '' He argued that `` the longing for freedom and human dignity '' is `` universal , and it beats in every heart . '' And he linked this year 's uprisings against regimes across the Middle East to the fall of Communism in Europe , of white minority rule in South Africa , and of dictatorships in Latin America and Southeast Asia , saying they reflect `` a longing for the same freedoms that we take for granted at home . '' Obama to Middle East : We 'll show you the money . He also contended that the rise of China , India and Brazil was linked to their acceptance of free markets on the British and American models . Their ascendance does not mean that Western leadership is in decline , he insisted , saying : `` The time for our leadership is now . '' His aides billed the address as the centerpiece of his six-day trip to Europe this week . British lawmakers greeted him with a standing ovation , and applauded his description of himself as the son of a Kenyan cook in the British army who had become president of the United States . The speech caps a two-day trip to Britain that mixed pomp with politics . Queen Elizabeth II hosted a state dinner for Obama Tuesday night , where he wore a white tie and tails , while a day later he and David Cameron rolled up shirtsleeves and served burgers and sausages to military service members and their families in the garden of 10 Downing Street . The president and prime minister turned up the heat on Moammar Gadhafi in a joint appearance Wednesday , with the president saying that `` ultimately '' the Libyan leader will go . The United Nations-endorsed mission to protect Libya 's people from their leader means making sure Gadhafi `` does n't have capacity to send in a bunch of thugs to murder innocent civilians and threaten them , '' Obama said . `` I do think we have made enormous progress in Libya . We have saved lives . Gadhafi and his regime need to understand there will not be a letup in the pressure we are applying , '' Obama said . But both he and Cameron said it will take time to reach a solution in Libya , which Gadhafi has ruled for 42 years . The nation seems to be grinding into a stalemated civil war . `` We may have to be more patient than people would like , '' Obama said . Cameron refused to answer a journalist 's question about whether the United Kingdom would send attack helicopters to bolster the military mission in Libya , but said : `` We should be turning up the heat in Libya , '' and vowed to look at `` all the options '' for doing so . Obama and Cameron were speaking on a wide range of topics at a news conference in a sunlit garden in London . Before their meeting with journalists , the two leaders discussed policy in Afghanistan and Pakistan and the Israel-Palestinian conflict , among other issues . Obama said America 's relationship with Britain is `` the strongest it has ever been '' and said the two nations are committed to working together on global economic recovery and fighting the war on terror . Cameron said the U.S. killing of al Qaeda leader Osama bin Laden was `` a strike right at the heart of international terrorism '' and that Britain and the United States must work closely with Pakistan in the future . `` We can defeat al Qaeda , '' Cameron said . Obama is in the middle of a six-day , four-nation trip to Europe that began in Ireland and will continue with stops in France and Poland . On Tuesday the president and first lady toured Buckingham Palace and visited Westminster Abbey , where crowds that had gathered along the roads outside cheered their arrival . Cameron talked up the two countries ' closeness the night before the Obama visit officially began , calling the relationship `` essential '' and saying there is an `` incredible alignment of views '' between 10 Downing Street and the White House . On a less formal note , Obama also joined Cameron in playing table tennis against two students during a visit to a local school . No details on the final score were made public , but the students won handily . CNN 's Richard Allen Greene contributed to this report .
The United States and Britain will `` stand with those who struggle , '' Obama says . He strongly defends U.S. leadership and values in a major speech to Parliament . Obama is in the middle of a two-day state visit to Britain blending pomp and politics . Queen Elizabeth II hosted a state dinner for him , while David Cameron helped him serve burgers .