South Korean President Lee Myung-bak left Washington for Detroit Friday after summit talks with U.S. President Barack Obama and an address to Congress that emphasized the significance of the alliance and a free trade agreement between the two countries. Lee is scheduled to make a three-hour stopover in Detroit, the heart of the U.S. auto industry, to visit a car plant together with Obama in what will be a symbolic gesture underlining their commitment to the trade pact approved by Congress on Wednesday. Lee will then head to Chicago, Obama\'s political hometown, for a dinner meeting with business leaders of the two countries hosted by Chicago Mayor Rahm Emanuel, who served as Obama\'s chief of staff. The trade accord is expected to be a key topic there also. Lee is scheduled to spend a night in Chicago before heading home on Saturday. Earlier in the day, Lee met with a dozen U.S. experts on security on the Korean Peninsula, including former U.S. Defense Secretary William Cohen, former National Security Advisor Stephen Hadley and former Deputy Secretary of State James Steinberg. The American experts told Lee that the trade deal will serve as a crucial watershed to elevate relations between the two countries and put forward their views on ways to deepen the alliance and cooperation on North Korea, and other regional and global issues, the presidential office said in a statement. Lee responded by asking them to pay continued attention to moving the alliance forward, it said.