SEOUL (Reuters) - South Korean President Moon Jae-in said on Thursday that North Korea’s criticism of the United States after recent talks on denuclearisation was part of its strategy and negotiations between them are on the “right track”.

South Korea’s President Moon Jae-in inspects an honor guard with Singapore’s President Halimah Yacob during a visit at the Istana in Singapore July 12, 2018. REUTERS/Edgar Su

North Korea accused the United States on Saturday of making “gangster-like” demands in the talks in North Korea late last week, contradicting U.S. Secretary of State Mike Pompeo who said the old enemies had made progress.

Moon, speaking in Singapore with its president and prime minister, said that talks on the denuclearisation of the Korean peninsula between North Korea and the United States may face hurdles and take time, his office said.

“No one can be optimistic about the results, but my cautious outlook is that the negotiations would be able to succeed if the North carries out a complete denuclearisation, and the international community gathers efforts to provide security guarantees to the North,” Moon said.

The North’s criticism was a “strategy” meant to show its frustration about what it sees as a lack of action from the United States in response to the steps it had recently taken, Moon said.

The North has invited foreign journalists, but not experts as promised, to the dismantling of a nuclear site, and pledged to close a missile engine testing facility.

The United States and South Korea have halted annual joint military exercises that North Korea has for years objected to.

Pompeo also said the two sides had agreed to hold discussions on Thursday at the inter-Korean border village of Panmunjom on the repatriation of remains of Americans killed in the 1950-53 Korean War.

But no one showed up from the North, South Korea’s Yonhap news agency said, citing a government official.

The return of U.S. remains was one of the key agreements to come from U.S. President Donald Trump’s June summit with North Korean leader Kim Jong Un.

A U.S. State Department spokesman declined to comment on Thursday except to note that Pompeo had said after his talks in Pyongyang that the date for the meeting to discuss the repatriation of remains was flexible.

Pompeo said just before leaving Pyongyang last Saturday that the meeting was set for July 12, but “could move by one day or two”.

South Korea’s Yonhap news agency reported that North Korea had called for general-level military negotiations to discuss the return of U.S. remains.

Citing an unidentified South Korean official, Yonhap reported that the North Koreans wanted to speak with an American general, possibly as early as Sunday.

Neither U.S. nor South Korean officials would immediately confirm the report.

Moon said North Korea wanted the United States to take action to end hostile relations and build trust.

He said he saw a big difference in North Korea’s attitudes to talks. In the past, it had demanded sanctions relief and economic concessions first, he said.