MANILA - U.S. Defense Secretary Mark Esper said on Tuesday he believed South Korea "can and should" contribute more on cost-sharing for hosting the U.S. military, after Seoul broke off the talks earlier in the day following a public backlash.Asked if he was willing to withdraw any U.S. forces if an agreement is not reached, Esper declined to say what the United States might do, adding that the U.S. State Department was leading negotiations."I'm sure it's in capable hands," Esper said during a trip to the Philippines, referring to the negotiations."South Korea is a wealthy country. They can and should contribute more. And beyond that I will leave it to the State Department to work out the particulars."