North Korea has reportedly replaced guards and fortified a section of its border with South Korea where a North Korean soldier staged a daring defection last week, while South Korean and U.S. soldiers have been decorated for their role in his rescue.

The North Korean defector was shot and wounded by his fellow soldiers as he dashed into the South Korean side of the Joint Security Area (JSA) last week.

The South Korean and U.S. soldiers who led a rescue attempt to drag the gravely injured soldier to safety have been awarded medals, according to U.S. Forces Korea.

At the United Nations, diplomatic sources said Friday that North Korea recently called for a new dialogue channel, but U.S. opposition has put the move in limbo.

Pyongyang made the overtures when its foreign minister, Ri Yong Ho, met with U.N. Secretary-General Antonio Guterres at U.N. headquarters in New York on Sept. 23, the sources said.

It is believed that North Korea wants to use the dialogue channel with the U.N. Secretariat to argue that rounds of U.N. Security Council sanctions resolutions imposed on it are unjust.

However, the U.S. side conveyed its opposition to the move, apparently out of concern that North Korea will aim to use the dialogue as a tool to justify its nuclear and missile programs.

A group of senior diplomats based in Seoul visited the JSA on Wednesday morning, where they saw five North Korean workers digging a deep trench in the area where the soldier had dashed across the line after getting his jeep stuck in a small ditch, a member of the diplomatic delegation said Friday.

In a photograph of the visit posted to the Twitter account of Marc Knapper, the acting U.S. ambassador in Seoul, North Korean workers could be seen using shovels to dig a deep trench on the North Korean side of the line as other soldiers stood guard.

“The workers were being watched very closely by the KPA guards, not just the two in the photo, but others out of shot behind the building,” said the diplomat, who asked not to be identified because of the sensitivity of the situation.

According to an intelligence official cited by South Korea’s Yonhap news agency, the North has replaced the 35 to 40 soldiers on guard duty at the JSA when the incident happened.

“We’re closely monitoring the North Korean military’s movement in the JSA,” a South Korean Defense Ministry official told reporters, without confirming the reduction in border guards. “There are limits as to what we can say about things we know.”

Reuters was unable to independently verify the reports, although photos taken by Knapper and other diplomats of soldiers guarding the area where workers were digging the trench showed them to be wearing slightly different uniforms to the ones usually worn by North Korea’s JSA guards.

Two new trees have also been planted in the small space between the ditch and the line with the South, the diplomat said, in an apparent effort to make it more difficult for would-be defectors to attempt to drive a vehicle across the border.

Meanwhile, in South Korea, U.S. Forces Korea (USFK) said it had awarded its own JSA soldiers — three South Korean and three U.S. soldiers — the Army Commendation Medal in recognition for their efforts in rescuing the defector.

The medals were personally handed out by USFK commander Gen. Vincent Brooks at a ceremony Thursday.

The soldiers dragged the wounded North Korean soldier to safety in a daring rescue seen in security camera footage released by the United Nations Command earlier this week.

Pyongyang has not commented on the defection of its soldier, who is now in stable condition despite sustaining multiple injuries sustained from gunshot wounds to his arm and torso.