It also comes amid some concerns in Washington about the enthusiasm with which South Korean President Moon Jae-in has embraced North Korean leader Kim Jong Un, despite the fact that North Korea has so far taken no concrete steps to disarm.
Plans to establish road and rail links were a key part of the agreement reached between Moon and Kim when they first met at the border village of Panmunjom in April.
The commitment to move ahead on the transport links was announced after high-level talks Monday between the two sides, at which they also agreed to hold a series of discussions on other areas of cooperation in coming weeks.
Talks are planned this month and next about increasing military engagement to reduce the threat of conventional warfare, about a joint bid to host the 2032 Summer Olympics and about stepping up contacts between families divided by the 1950-53 Korean War.
Lim Eul-chul, an expert on the North Korean economy at South Korea's Kyungnam University, said the tight timeline for the groundbreaking ceremony reflects Pyongyang’s determination to make rapid progress on talks over denuclearization.
But it also reflects the North’s efforts to have sanctions lifted as soon as possible, a position with which Moon appears to sympathize.
“Once North Korea reaches a certain stage in the denuclearization process, from that point on, gradual relief of economic sanctions on North Korea should also be seriously considered,” Moon told the BBC in an interview last week.
Secretary of State Mike Pompeo met Kim last week and came away saying that the leaders of North Korea and the United States both believed they could make “substantive progress” at a second summit meeting. But no date for that summit has yet been set, with President Trump saying it could only happen after the Nov. 6 midterm elections.
The United States has repeatedly insisted that sanctions will be lifted only after North Korea completely and verifiably dismantles its nuclear weapons program.
Moon’s government takes a different view, preferring a phased process in which both Pyongyang and Washington take gradual steps together.
Last week it proposed to lift some unilateral sanctions it imposed on the North over the sinking of a naval ship in 2010, provoking a curt retort from Trump that Seoul could “do nothing without our approval.”
Seoul walked the proposal back the following day.
South Korean Foreign Minister Kang Kyung-wha also told lawmakers last week that Pompeo expressed displeasure about agreements reached by Moon and Kim to reduce conventional military threats and asked a number of questions about the deal “since he hadn’t been adequately briefed.”
South Korean media reported last week that the U.S. Treasury Department held conference calls with several banks in Seoul last month warning them not to violate the sanctions.
In another sign of frustration with the sanctions in Pyongyang, the North Korean newspaper Rodong Sinmun last week accused the country’s enemies of implementing “a murderous blockade” after their bid to suffocate the country militarily had failed.
Even if the sanctions are imposed for a decade or a century, North Korea will overcome them “to emerge as the world's strongest power and socialist paradise,” it wrote.
Kim reported from Seoul.