WASHINGTON, April 12 (UPI) -- Two former American diplomats who played a key role in the Six Party Talks with North Korea warned Thursday that President Donald Trump should make no compromise on sanctions during his upcoming summit with Kim Jong Un.
Christopher Hill, who served as the U.S. ambassador to Iraq under President Barack Obama, and Victor Cha, an adviser on North Korean affairs to President George W. Bush, said any misstep at the summit could endanger stability in Asia.
"If this summit fails, it could take us a step closer to armed conflict, and without adequate preparation there's a greater chance of failure," Cha said Thursday during a hearing before the House Foreign Affairs Committee.
During the first Six Party Talks in 2005, North Korea made a commitment -- unprecedented at the time -- to abandon nuclear weapons and programs and return to the treaty of nonproliferation.
But North Korea soon withdrew from the discussions and began a series of nuclear tests in May 2009, dashing diplomatic hopes of disarmament on the Korean Peninsula.
Cha and Hill told the committee the complete denuclearization of North Korea isn't likely. However, they stressed that at the upcoming summit, Trump must avoid any concessions that weaken the sanctions on North Korea.
"The United States must continue the application of its sanctions," Cha said.
"Our goal is to make sure sanctions aren't off the table," Rep. Ted Yoho, R-Fla., said.
Cha and Hill also cautioned against neglecting allies' interests in the region.
If conflict were to break out on the Korean Peninsula, more than 25 million people could be at risk, Rep. Gerry Connolly, D-Va., said, including 25,000 American troops.
"This is a testimony to our allies...we want to go in with a policy benefiting all of us in the region and not separating us from our allies," Cha said.
South Korean President Moon Jae-in, preparing for his own meeting with Kim Jong Un on April 27, sent his national security adviser to Washington to meet with his U.S. counterpart, John Bolton, on Thursday.
Bolton has advocated a pre-emptive military strike against North Korea, as outlined in a Wall Street Journal op-ed in February, before his appointment to the Trump administration.
Preparations for the high-stakes summit come as key diplomatic positions remain vacant. Trump has not appointed an ambassador to South Korea. Special Representative for North Korea Policy Joseph Yun recently retired.
"Successful diplomatic negotiations will require a fully resourced and staffed State Department, a robust interagency team and a disciplined strategy," Connolly said. "The Trump Administration is woefully unprepared on each of these fronts."
Even Trump's nominee for secretary of state, CIA Director Mike Pompeo, expressed concerns about the lack of preparation for the president's meeting with Kim during his Senate confirmation hearing Thursday.
"I will start with those things that I think are the biggest risk to America's capacity to execute its diplomacy," Pompeo told the Senate Foreign Relations Committee. "We don't yet have an ambassador to South Korea, we need one."