The U.S. and South Korea should open up two-track “direct discussions” with North Korea, U.S. Senator Edward J. Markey suggested on Tuesday.

Markey (D-Mass.) who is currently leading a high-profile congressional delegation to the South, said he agreed with President Moon Jae-in that the U.S should aim to “peacefully resolve” the North Korean nuclear issue.

At a news conference held in Seoul following talks with Moon on Monday evening, Markey suggested four principles on which Washington’s North Korea policy should be based.

The U.S. “must begin direct discussions with North Korea on two closely coordinate tracks” with South Korea, the Senator