ROME – In what is being dubbed a “surprising development,” U.S. President Donald Trump Sunday became the first American commander-in-chief to set foot in North Korea, at the invitation of Kim Jong Un.

According to Pope Francis, speaking shortly after the meeting, it was an example of the “culture of encounter.”

“In the last few hours we have witnessed a good example of the culture of encounter in Korea,” Francis said Sunday.

“I greet the protagonists with the prayer that this significant gesture constitutes a further step on the path of peace. Not only on that peninsula but in favor of the whole world.”

The pope’s words came at the end of his traditional Angelus prayer, which he delivered from one of the windows of the papal apartments overlooking St. Peter’s Square.

Trump crossed a low stone curb that separates the two Koreas a little before 4:00 p.m. local time. Though he only took some 20 steps into North Korea, he made history by becoming the first serving U.S. president to do so.

The gesture, which was broadcast live, seemed to be spontaneous. Afterwards, the U.S. president said he was “proud to step over the line,” and thanked Kim for the meeting.

He also said he’d invited the Korean leader to the White House, acknowledging however that such a visit would not be happening any time soon.

Earlier Sunday, Trump held a bilateral meeting, a working lunch and a press conference with South Korean President Moon Jae-in in Seoul.

The meeting between Trump and Kim was organized on Saturday, both leaders confirmed, after Trump sent a tweet to the Korean leader suggesting they meet and “say Hello(?)!” The U.S. president was in the area participating in the G20 summit in Osaka.

Trump travelled to the demilitarized zone with the South Korean leader, and the three had an hour-long meeting at Peace House, which technically belongs to the southern side of the peninsula.

Trump and Kim had met twice before: last June and earlier this year.

Follow Inés San Martín on Twitter: @inesanma

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