Pakistan and the United States Saturday called for a clearly defined strategic partnership to act jointly against terrorism and for regional peace. The call was made during a series of talks between visiting U.S. Special Representative for Afghanistan and Pakistan Ambassador Marc Grossman and top Pakistani leaders over the past two days. Ambassador Grossman met President Asif Zardari, Prime Minister Raja Pervez Ashraf, Foreign Minister Hina Rabbani Khar and other high-ranking officials. The Prime Minister's Office said that Pervez Ashraf and the U.S. envoy discussed matters concerning bilateral relations. The Prime Minister said that Pakistan-U.S. relations are very important and his country values the United States as a major development partner, a PM office statement said. Ambassador Grossman said that the United States believes that its relationship with Pakistan should be enduring, strategic and clearly defined. Meanwhile, a report published today by Dawn news said Marc Grossman concluded his two-day visit to Pakistan on Saturday. Grossman was in Pakistan for preparing groundwork for Foreign Minister Hina Rabbani Khar's trip to Washington. Ms Khar, who will pay an official visit to the US from Sept 18 to 22, will meet Secretary of State Hillary Clinton, National Security Adviser Tom Donilon and US Trade Representative Ambassador Ron Kirk. It is expected that Pakistan and the US may agree on a document during Ms Khar's Washington visit setting the terms for future cooperation.