Mark Esper speaks to reporters during a briefing at the Pentagon. File photo/ AP

US Defense Secretary Mark Esper said on Thursday he does not regret postponing a US-South Korean military exercise, even though the gesture was rejected by North Korea as not enough to restart nuclear diplomacy.

The prospects for a resumption of the nuclear diplomacy are unclear, with Pyongyang stepping up its pressures on Washington to make bigger concessions. On Wednesday, the North’s 1st vice foreign minister, Choe Son Hui, repeated it won’t return to a negotiating table unless the United States drops its hostile policy against the North.

“We can discuss the nuclear issue with the US only when it withdraws all its hostile polices against (North Korea),” Choe told reporters during a visit to Moscow, according to South Korean media footage. “In that sense, I think a summit or leaders’ talks (between North Korea and the US) aren’t an interesting issue for us.”

The US and South Korea announced Sunday they indefinitely postponed the annual Vigilant Ace aerial training as part of efforts to revive the nuclear talks, as North Korea has called the training an invasion rehearsal. In response, senior North Korean official Kim Yong Chol said Tuesday the US must scrap that military drill completely and abandon its hostility against his country if it wants to see the resumption of the nuclear negotiations.

North Korea wants the US to lift major international sanctions on it and provide security assurances before it fully abandons its nuclear arsenal. But the US has maintained sanctions would stay in place until North Korea takes serious steps toward denuclearization.

Before boarding his plane in Hanoi, Vietnam, for a flight to Washington, Esper described North Korea’s response to the drill’s postponement as being “not as positive as we would have liked.” In Esper’s words: “I don’t regret taking the high road.”

Esper also said he does not believe there is a rift in the US-South Korean alliance, despite a breakdown this week in negotiations over a US demand for a five-fold increase in what Seoul pays to keep 28,500 American troops on its soil.

He said he was not aware of a plan, reported in South Korean media, that the US is considering withdrawing some of its troops from South Korea if Seoul doesn’t agree to that increase. Esper said Gen. Mark Milley, chairman of the Joint Chiefs of Staff, has not mentioned any such plan in their recent talks.

“We’re not threatening allies over this,” Esper said.

On Thursday, South Korea’s biggest newspaper, Chosun Ilbo, cited an unidentified diplomatic source in Washington as saying the US is mulling pulling out a brigade from South Korea if the cost-sharing negotiations faltered. It said an American brigade usually has 3,000-4,000 troops.

A US-led diplomacy aimed at ridding North Korea of its nuclear weapons has largely been deadlocked since the February collapse of a summit between President Donald Trump and North Korean leader Kim Jong Un. Kim Jong Un has demanded the US come up with new, acceptable measures to salvage the nuclear talks by year’s end.

Associated Press