North Korea’s Ri Yong Ho arrived in Stockholm on Thursday for talks with his Swedish counterpart Margot Wallstrom amid a flurry of diplomatic activity concerning the reclusive country and its nuclear ambitions.

Trump reaffirmed on Friday that he was willing to meet Kim after South Korean officials passed on an invitation earlier this month. North Korea has so far not publicly acknowledged the invitation.

“The foreign ministers discussed opportunities and challenges for continued diplomatic efforts to reach a peaceful solution to the conflict as well as bilateral relations,” the Swedish foreign ministry said in a statement after Ri and Wallstrom wound up their talks.

“Sweden underlined the need for North Korea to dismantle its nuclear arms and missiles program in line with several Security Council resolutions.”

No U.S. government officials participated in the talks this week in Sweden, a State Department official said.

The Central Intelligence Agency has taken the lead on organizing potential discussions between the U.S. and North Korea, The New York Times reported on Saturday. The head of the CIA, Mike Pompeo, has been named as a successor to run the State Department in the wake of the ouster of Secretary of State Rex Tillerson.

The talks in Stockholm had initially been scheduled to conclude on Friday but were extended into the weekend.

“The dialogue has been constructive,” a source with knowledge of the discussions said. “It should be seen as a positive sign that the meeting was extended (until Saturday).”

The source said that Sweden had been in close touch with the United States and South Korea before the Stockholm meetings and hoped the talks would lead to further progress towards defusing tensions.

“Sweden will continue to do what it can, but it is the protagonists themselves who have to drive the process forward,” the source said.

In the wake of the Stockholm talks, Wallstrom will meet her South Korean counterpart Kang Kyung-wha, who was in Washington this week for talks on North Korea and trade, in Brussels on Monday, Wallstrom’s spokesman said.

Sweden is one of a handful of countries considered a possible venue for a meeting between Trump and Kim, who have engaged in bellicose mudslinging over North Korea and its nuclear arms program.

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