SEOUL, South Korea (AP) — South Korean officials have traveled to North Korea by train to attend a groundbreaking ceremony for an aspirational project to modernize North Korean railways and roads and connect them with the South.

Wednesday’s ceremony at the North Korean border town of Kaesong comes weeks after the Koreas conducted a joint survey on the northern railway sections they hope to someday link with the South.

The ambitious project is among a variety of peace gestures agreed between North Korean leader Kim Jong Un and South Korean President Moon Jae-in as they push ahead with engagement amid a stalemate in larger nuclear negotiations between Washington and Pyongyang.

But beyond on-site reviews and ceremonies, the Koreas cannot move the project much further along without the removal of U.S.-led sanctions against the North.