WASHINGTON (Reuters) - The United States and China unveiled $45 billion in export deals on Wednesday as Presidents Barack Obama and Hu Jintao sought to paper over deep rifts about trade, currencies and security. Amid the pomp of a state visit, Obama and Hu vowed to seek common ground as they launched talks aimed at easing the strains of the past year over North Korea, economic imbalances, human rights, Taiwan, Tibet and a host of other issues. Welcoming Hu to the White House, Obama hailed the event as a chance to demonstrate that the worlds two biggest economic powers have an enormous stake in each others success. Even as our nations compete in some areas, we can cooperate in others, Obama said at the choreographed welcoming ceremony. Let us seize these possibilities together. The two countries used the summit to unveil a series of deals, including Chinas purchase of 200 Boeing aircraft. US officials said the $45 billion in deals would support an estimated 235,000 American jobs. Obama wants the visit to help highlight his efforts to boost the struggling US economy and cut unemployment that has been persistently above 9 percent. Offering another tangible achievement, the United States and China plan to announce a deal to create a jointly financed security centre in China. Obama and Hu were also due to attend a meeting of US and Chinese business leaders at the White House. But in a major concern for US companies and lawmakers, Beijing has so far resisted demands for faster appreciation of its currency, the yuan, that would possibly help lower Chinas trade surplus with the United States, which Washington puts at $270 billion. Gently raising Chinas human rights record, Obama said: History shows that societies are more harmonious, nations are successful and the world is more just when the rights and responsibilities of all nations and all people are upheld, including the universal rights of every human being. Hu said he had come to enhance mutual trust and open a new chapter in relations but signalled he would bristle at any effort to push China on its currency practices, human rights and other disputes that it deems to be domestic matters. China and the United States must respect each others choices in development and each others choices in development paths and each others core interests, Hu said. Hu was greeted with a 21-gun salute, honour guards and the playing of both national anthems in a show meant to convey recognition of Chinas growing international stature. US Secretary of State Hillary Clinton called for more cooperation from China in dealing with North Koreas nuclear program and provocative behaviour. She also said the Obama administration was pressing Beijing very hard to gets its entities into compliance with UN sanctions on Iran.