Last month, similar surveys were conducted for two railways and one highway in the North after the UN Security Council granted sanctions exemptions for them.

"A sanctions exemption procedure is under way for the joint road survey," a ministry official said.

The South has filed for a waiver with the Security Council after discussing the issue with the United States at a recent meeting of their joint working group on North Korea, sources said.

Once a waiver is granted, the South plans to discuss with the North specific schedules of the survey.

Modernizing two North Korean railways and two highways running along the rail lines, and linking them to the South is part of an agreement that South Korean President Moon Jae-in and North Korean leader Kim Jong-un made at their first summit in April last year.

Last month, the Koreas held a groundbreaking ceremony in a symbolic display of their commitment to pursue the reconciliation project. But it is unclear when actual construction will begin because sanctions must first be waived or lifted for the massive project following progress in denuclearization negotiations between the US and the North. (Yonhap)