Professor at Seoul's University of North Korean Studies Yang Moo-jin comments after North and South Korea signalled a surprise thaw in relations on Tuesday, announcing the restoration of cross-border communications that were severed more than a year ago and an agreement between their two leaders to improve ties. "Through the restoration of of cross-border communications, it is likely that President Moon Jae-in will again become a mediator in future U.S.-North Korea talks," he says. IMAGES AND SOUNDBITES