Updated

A U.S. special envoy for North Korea on Thursday visited a border village the rival Koreas has been demilitarizing as part of steps to reduce military tensions amid a larger diplomatic push to resolve the nuclear crisis.

The U.S. Embassy in Seoul did not provide details about Stephen Biegun's visit to Panmunjom. He wasn't expected to meet with North Korean officials at the village, which is often used for diplomacy between the allies and North Korea.

Biegun said after arriving in South Korea on Wednesday that Washington was reviewing easing travel restrictions on North Korea to facilitate humanitarian shipments to help resolve an impasse in nuclear negotiations.

North Korea hasn't responded to Biegun's comments. The North's state media recently warned that the United States' continued commitment to sanctions and criticism about the North's human rights record could "block the path to denuclearization on the Korean Peninsula forever."

During his four-day visit to South Korea, Biegun plans to discuss with South Korean officials the allies' policies on North Korea, including the enforcement of sanctions. The meetings are likely to include conversations about a groundbreaking ceremony the Koreas plan to hold at Panmunjom next week for a project to reconnect their roads and railways.

The nuclear negotiations between Washington and Pyongyang have stalled since a summit between President Donald Trump and North Korean leader Kim Jong Un in June, when they issued a vague promise for a nuclear-free Korean Peninsula without describing how or when it would occur. The United States wants North Korea to provide a detailed account of nuclear and missile facilities that would be inspected and dismantled under a potential deal, while the North is insisting that sanctions be lifted first.

The stalemate has been a setback for liberal South Korean President Moon Jae-in, who has been actively pushing for reconciliation with the North. Washington and Seoul also have disagreed over the pace of inter-Korean engagement, which Washington says should move in tandem with U.S.-led efforts to denuclearize the North.

Through three summits between Moon and Kim this year, the Koreas agreed to a variety of goodwill gestures and vowed to resume economic cooperation when possible, voicing optimism that international sanctions could end to allow such activity. The rivals have also taken steps to reduce their conventional military threat, such as removing mines and firearms from Panmunjom, destroying some front-line guard posts and creating buffer zones along their land and sea boundaries and a no-fly zone above the border.