WASHINGTON, U.S. President Donald Trump said Friday he would be "very disappointed" if North Korea resumed the testing of nuclear weapons and ballistic missiles, but insisted his relationship with North Korean leader Kim Jong-un remains good.

Speaking to reporters at the White House, Trump appeared to address a question about recent reports of reassembly at a key North Korean missile site.

"Well, time will tell, but I have a feeling that our relationship with North Korea, Kim Jong-un and myself, Chairman Kim, I think it's a very good one. I think it remains good," he said.

"I would be surprised in a negative way if he did anything that was not per our understanding, but we'll see what happens."

Trump and Kim held their second summit in Hanoi, Vietnam, last week but failed to produce any agreement on the North's denuclearization.

This week, two U.S. think tanks said in separate reports that commercial satellite imagery shows the North rebuilding the missile engine testing site in Dongchang-ri, which it began to dismantle last year.

Trump said initially he would be "very, very disappointed" with Kim if the reports are true. On Thursday he added he is "a little disappointed."

"Let's see what happens, but I would be very disappointed if I saw testing," he said Friday.

Source: Yonhap news Agency