South Korean President Moon Jae-in arrived on Tuesday in the North Korean capital of Pyongyang for the third summit of the year between the two Koreans. While the other visits were highly aspirational, this summit has a more direct goal – reaching a peace treaty.

Moon was very frank about this, saying “what I want to achieve is peace. Not a tentative change which could be volatile dependent on international situation, but irreversible, permanent, and unwavering peace, regardless of what might happen on the global area.”

That’s likely to be difficult, with the Trump Administration having made clear repeatedly in recent months that they aren’t willing to reach a peace deal yet, and are intending to hold that out as something North Korea can only get after years of additional concessions.

North Korea has resisted giving up any more without being certain they’ll get a peace deal, ending the Korean War that began in 1950. Likewise, South Korea’s President Moon has set himself up as wanting such a deal, with or without US endorsement.

This risks a split between the US and South Korea, as the two sides have seen differences shaping up in the past several months on how to approach North Korea diplomacy, and the US has increasingly chosen to negotiate independent of the wishes of its long-time allies in South Korea.