North Korean Foreign Minister Ri Yong Ho had originally been scheduled to hold two days of talks with Wallstrom in Stockholm.
Prime Minister Stefan Lofven said the rumours that Sweden could possibly host a summit were premature.
"We value this opportunity to arrange a meeting".
Earlier, Lofven had said that Stockholm is willing to host the historic summit.
"We've made a decision to narrow down the summit agenda and focus the talking points on securing permanent peace on the Korean Peninsula through denuclearization and dramatic reduction of military tensions and on drawing up ways for new, bold progress in inter-Korean relations".
"If we can help and provide a forum for this and support this process, then this is something we should do".
South Korean-born Yun, a strong advocate for engagement with Pyongyang, led contact with North Korea and quietly pursued direct diplomacy since taking his post under former President Barack Obama in 2016.
"The ministry said talks "will focus on Sweden's consular responsibilities as a protecting power for the United States, Canada and Australia", but also will also address the security situation on the Korean Peninsula".
The 2 leaders held phone talks on Friday.
"I've talked to North Korea and I sent a single message to them, which was that this was an incredible opportunity for both sides and they need to respond", Yun told CNN.
Kim has also pledged to suspend missile and nuclear activities during the period of dialogue with Washington, according to the South Korean government.
According to the ministry, the Japanese side noted South Korea's leading role in the diplomatic achievements.
There was no official word from North Korea since the invitation was delivered via South Korean officials in Washington.
"It is necessary to maintain close coordination (between South Korea and the U.S.) at various levels in making preparations for critical diplomatic events going forward", Kang said.
Im added Moon may meet Trump after the inter-Korean summit but before Trump's planned summit with Kim in May.