Such a declaration wouldn’t be a formal peace treaty or replace the armistice, which would require assent from all the signatories of the ceasefire, including China and the United Nations Command. But South Korea’s president Moon Jae-in has argued that a joint statement would start the process of officially ending the Korean War.

“It’s a meaningless, feel-good gesture that carries risks with it,” Bruce Klingner, a research fellow at The Heritage Foundation, a conservative think-tank in Washington, and a former senior CIA official specializing in Korea. “If it’s given in return for freezing Yongbyon. That’s a new price we’ve paid for something we’ve gotten several times before,” Klingner said, referring to North Korea’s promise to dismantle the Yongbyon Nuclear Scientific Research Center in earlier peace negotiations. Klingner believes the U.S. should not sign a peace declaration while North Korea still has a nuclear program.

In addition, Klingner argues, declaring the war over would open the U.S. up to pressure to remove its 28,000 troops stationed on the Korean peninsula, a long-term goal of the North Korean leadership, and one that Trump himself has long agreed with, though it would be a break with decades of bipartisan agreement in Washington. Researchers at the Center for Strategic and International Studies found scores of statements Trump has made over the years expressing skepticism of the value of keeping American troops in South Korea.