Last week the UN Security Council agreed to partially waive the sanctions on North Korea for a project to reconnect its railways with those of the South and to modernize them.
Now the U.S. has granted an exemption to its sanctions for the project.
Sources in the South Korean government tell Yonhap News on the condition of anonymity that the sanctions waiver from Washington has been finalized in talks with Seoul.
The U.S. has been imposing unilateral sanctions on North Korea in addition to the international ones, and those sanctions ban the transfer of refined petroleum products to the North -- something that would be needed for the project.
The two Koreas are expected to start work on it next week.