Set against a tense, eerie silence in the landmine-riddled mountains separating South Korea and North Korea, the Demilitarized Zone may be the highest-stakes negotiation site on Earth. It is not the sort of place for mistakes.

It is the latest spot where Ivanka Trump has tried her hand at statecraft.

On Sunday, Ivanka Trump, the president’s elder daughter, used an impromptu meeting between her father and Kim Jong Un, the North Korean leader, to further slip into the role of unofficial spokeswoman and budding stateswoman for the Trump administration. With her husband, fellow senior adviser Jared Kushner, at her side, Ivanka Trump delivered news interviews, posed for photographs and attended a closed-door meeting between her father and Kim.

Earlier in the day, Ivanka Trump had repeated what her father has often said about dealing with the North: that it would be free of crippling sanctions and clear for an economic boom if Kim were to dismantle his nuclear program. Scant evidence suggests that Kim is taking the steps to do this, but Sunday, two Trumps rewarded him with a visit.

“We are on the precipice of ushering in potentially a golden era for the Korean Peninsula,” Ivanka Trump told Bloomberg News in the hours before her father took the historic step of crossing into the North. But by the time she emerged from the closed-door meeting between the leaders hours later, she only had one word for journalists about her encounter with North Korea.

She called it “surreal.”

Others following along called it inappropriate.

“Ivanka Trump is not on the National Security Council — she is not an adviser on the issues being discussed,” Michael A. McFaul, an ambassador to Russia under former President Barack Obama, said of Ivanka Trump’s presence. “So her presence undermines the professional look of the Trump delegation, both to other countries and to national security professionals in the Trump administration.”

President Donald Trump has come under fire for making family members part of his staff since the beginning of his administration, and then for clinging more tightly to them in a White House racked by turnover. Kushner alone has overseen portfolios ranging from the federal government’s outdated technology to peace in the Middle East. But for Ivanka Trump, 37, the visit to Asia over the past week represented a prominent step onto a bigger stage.

She was the most visible woman from the Trump administration to go. Her stepmother, first lady Melania Trump, stayed behind in Washington, and Sarah Huckabee Sanders, former White House press secretary and a fixture of recent overseas trips, had just stepped down.

So at the summit of the Group of 20 economic powers in Osaka, Japan — the original purpose of the trip before Donald Trump threw out a Twitter invitation to meet Kim at the Demilitarized Zone — Ivanka Trump was repeatedly flanked by her father and a roster of world leaders, including Shinzo Abe, prime minister of Japan, and Mohammed bin Salman, crown prince of Saudi Arabia.

Observers and critics used a snippet of digital footage as a way to show that she might be out of her depth: A short video posted to Instagram by the office of Emmanuel Macron, president of France, showed Ivanka Trump in conversation with Theresa May, the departing prime minister of Britain, and Christine Lagarde, the International Monetary Fund managing director, as Macron and Justin Trudeau, Canadian prime minister, listened.

In the clip, Ivanka Trump seemed to be looking to find a place to jump into this diplomatic game of double Dutch. First May spoke: “As soon as you charge them with that economic aspect of it, a lot of people start listening who otherwise wouldn’t listen.”

And then Ivanka Trump jumped in: “And the same with the defense side of it, in terms of the whole business that’s been, sort of, male dominated.”

Lagarde, who was standing next to the president’s daughter, swiveled her head and blinked several times as she listened.

Ivanka Trump has made international women’s empowerment a cornerstone of her work in the White House. In February, she unveiled the Women’s Global Development and Prosperity Initiative, a program meant to bring economic security to 50 million women across the world by 2025. In recent weeks, she has crisscrossed the country to bring attention to the Trump administration’s effort to bolster workforce development. And in Osaka last weekend, she told world leaders that women should be at the heart of any economic agenda.

Still, the video posted by the French led to rampant discussion online about which doors had been opened for Ivanka Trump because of her proximity to her father, and whether she should be engaging with heads of state at a diplomatic event. Among those criticizing her access was Rep. Alexandria Ocasio-Cortez, D-N.Y.

“It may be shocking to some, but being someone’s daughter actually isn’t a career qualification,” Ocasio-Cortez wrote on Twitter. “It hurts our diplomatic standing when the President phones it in & the world moves on.”

On Sunday, a White House official, who spoke on condition of anonymity to describe internal conversations, pushed back at the characterization that Ivanka Trump had interjected or annoyed others in the conversation — particularly Lagarde, who the official said had, like the others, been attending a women’s empowerment event where Ivanka Trump had been invited to speak when the interaction was filmed.

That official said Donald Trump had requested that his daughter accompany him to several G-20 events and even delayed the start of one so he would not miss her giving an introductory speech.

A White House deputy communications secretary, Jessica Ditto, called the video clip a “misrepresentation” and the criticism around it “absolutely pathetic” in an email. On Monday, Ditto added, “It is sad but not shocking that the haters choose to attack Ivanka Trump, a senior adviser to the president, when she is promoting U.S. efforts to empower women through strategic partnerships with world leaders.”

Gone are the days when Ivanka Trump and Kushner kept relatively low profiles inside the West Wing, grappling with waves of bad press as they sought to establish their profiles behind the scenes. And gone are the days when senior aides, such as John Kelly, the former chief of staff, tried to curb their influence.

Ivanka Trump’s participation in the G-20 trip illustrated just how unchecked her ascent in the White House has been in recent months.

If the president has any concern about his daughter playing diplomat, it did not show on this trip: During a meeting for troops at a military base outside Seoul, South Korea, the president introduced his daughter alongside Mike Pompeo, his secretary of state.

“She’s going to steal the show,” Trump said. “She’ll steal it.”

Glancing at his secretary of state and his daughter, Trump also offered his thoughts about her appearance: “Beauty and the beast, Mike,” he added.