South Korean President Park Geun-hye wrapped up her first visit to the United States on Thursday after reaffirming the two countries are firmly united against threats from North Korea and are committed to upgrading their six-decade-old alliance. Park and Obama agreed to deal sternly with North Korean provocations and work together to end the same old behavioral pattern of North Korea seeking to win concessions after saber rattling. They also repeatedly stressed how united they are on dealing with Pyongyang. Still, the two leaders said they are keeping the door for dialogue with North Korea open, and urged the communist nation to make the strategic decision to forgo its nuclear ambitions and become a responsible member of the international community. The summit was seen as helping expand U.S. understanding of Park's trademark policy on North Korea, known as the Korean Peninsula trust process, a two-track approach of pressure and flexibility that calls for fostering trust and reducing tensions on the divided peninsula. A joint declaration commemorating the 60th anniversary of the two countries' alliance also said that the sides will continue to try to bring North Korea into compliance with its international obligations and promote peace and prosperity on the Korean Peninsula, including through the trust-building process initiated by President Park. The joint declaration described the alliance between the two countries as "a linchpin in the Asia-Pacific," a coveted term that the U.S. used in the past to refer only to its alliance with Japan.