Kim Yo-jong, believed to be 30 years old, has become one of the most visible figures in her brother's regime since he took power.

She became the first member of the ruling dynasty to visit the South when she attended the Winter Olympics in February.

Ms Kim was at her brother's side as he walked across the line dividing the two Koreas.

She handed him a pen to sign a guestbook at the Peace House in the truce village of Panmunjom and joined him for the first round of talks with South Korean president, Moon Jae-in, where she took notes.

Later in the meeting, she was said to have blushed when Mr Moon described her as a celebrity after he appearance in Pyeongchang for the Winter Olympics.

Kim Yong-chol, North Korea's former intelligence chief and key figure when it comes to his country's dealings with the south, also attended the meeting.

Korea Summit: Kim Jong-un crosses border for historic meeting Show all 25 1 /25 Korea Summit: Kim Jong-un crosses border for historic meeting Korea Summit: Kim Jong-un crosses border for historic meeting North Korean leader Kim Jong-un and South Korean President Moon Jae-in raise their hands after signing on a joint statement Korea Summit Press Pool via AP Korea Summit: Kim Jong-un crosses border for historic meeting Kim Jong-un heads towards Moon Jae-in to shake his hand between the military demarcation line, at the Joint Security Area on the Demilitarized Zone in the border village of Panmunjom in Paju EPA Korea Summit: Kim Jong-un crosses border for historic meeting South Korean President Moon Jae-in and North Korean leader Kim Jong-un hold hands as they cross the military demarcation line EPA Korea Summit: Kim Jong-un crosses border for historic meeting South Koreans react while watching a screen reporting the Inter Korean Summit Getty Korea Summit: Kim Jong-un crosses border for historic meeting South Korean President Moon Jae-in and North Korean leader Kim Jong-un chat as they arrive at the Peace House Reuters Korea Summit: Kim Jong-un crosses border for historic meeting North Korea’s leader Kim Jong-un was escorted by bodyguards from the North to the Military Demarcation Line that divides the two Koreas to meet with his South Korean counterpart at the truce village AFP/Getty Korea Summit: Kim Jong-un crosses border for historic meeting North Korean leader Kim Jong-un crosses the military demarcation line to meet with South Korean President Moon Jae-in AP Korea Summit: Kim Jong-un crosses border for historic meeting Kim Jong-un and Moon Jae-in shake hands Getty Korea Summit: Kim Jong-un crosses border for historic meeting North Korean leader Kim Jong-un and South Korean President Moon Jae-in shake hands after Kim crossing the military demarcation line Getty Korea Summit: Kim Jong-un crosses border for historic meeting South Korean President Moon Jae-in and North Korean leader Kim Jong-un at the Joint Security Area EPA Korea Summit: Kim Jong-un crosses border for historic meeting South Korean President Moon Jae-in and North Korean leader Kim Jong-Un speak with two South Korean children who presented Kim Jong-un with a bouquet of flowers EPA Korea Summit: Kim Jong-un crosses border for historic meeting Moon Jae-in Kim Jong-un pose for photographers at the Joint Security Area (JSA) EPA Korea Summit: Kim Jong-un crosses border for historic meeting North Korean leader Kim Jong-un signs the guest book as South Korean President Moon Jae-in looks on Getty Images Korea Summit: Kim Jong-un crosses border for historic meeting North Korean leader Kim Jong-un’s entry in the guestbook. The writing reads ‘A new history starts now. An age of peace, from the starting point of history’ Korea Summit Press Pool/Pool via Reuters Korea Summit: Kim Jong-un crosses border for historic meeting South Korean President Moon Jae-In and North Korean leader Kim Jong-un talk during their summit meeting at the Peace House EPA Korea Summit: Kim Jong-un crosses border for historic meeting North Korea's leader Kim Jong-un smiles AFP/Getty Korea Summit: Kim Jong-un crosses border for historic meeting North Korean leader Kim Jong-un poses with South Korean President Moon Jae-in for a photo inside the Peace House AP Korea Summit: Kim Jong-un crosses border for historic meeting North Korea’s leader Kim Jong-un talks with South Korea’s President Moon Jae-in AFP/Getty Korea Summit: Kim Jong-un crosses border for historic meeting North Korean leader Kim Jong-un and South Korean President Moon Jae-in prepare to plant a pine tree near the military demarcation line AP Korea Summit: Kim Jong-un crosses border for historic meeting South Korean President Moon Jae-in and North Korean leader Kim Jong-un applaud after planting a tree at the truce village Korea Summit Press Pool/Pool via Reuters Korea Summit: Kim Jong-un crosses border for historic meeting North Korea’s leader Kim Jong-un and South Korea’s President Moon Jae-in take a walk after they planted a tree AFP/Getty Korea Summit: Kim Jong-un crosses border for historic meeting North Korea’s leader Kim Jong-un talks with South Korea’s President Moon Jae-in at a bench on a bridge next to the military demarcation line at the truce village of Panmunjom AFP/Getty Korea Summit: Kim Jong-un crosses border for historic meeting North Korean leader Kim Jong-un and South Korean President Moon Jae-in sign on a joint statement Korea Broadcasting System via AP Korea Summit: Kim Jong-un crosses border for historic meeting North Korean leader Kim Jong-un and South Korean President Moon Jae-in embrace each other after signing on a joint statement Korea Summit Press Pool via AP Korea Summit: Kim Jong-un crosses border for historic meeting North Korean leader Kim Jong-un, left, and South Korean President Moon Jae-in shake hands after their joint announcement AP

Ms Kim hit the headlines when she attended the games.

A picture of her shaking hands with Mr Moon at the opening ceremony in a seemingly impromptu moment as a joint North-South team marched into the Olympic Stadium, became one of its defining moments.

The South Korean leader appeared elated at the gesture and reciprocated warmly

South Korea's president, Moon Jae-in, greets Kim Yo-Jong, the sister of North Korea's leader, Kim Jong-il ahead of the inter-Korean summit (Korea Summit Press Pool/Getty Images)

The image of the two beaming with pride quickly became iconic, not least because it also showed the US vice president, Mike Pence, sitting stone-faced nearby.

Believed to be in charge of maintaining her brother's public image and the cult of personality which surrounds him, it is thought that Ms Kim is a close confidante of her brother.

She was appointed to the powerful Politburo - the most powerful body in the isolated regime's ruling party - last October.

Kim Yo-jong handed her brother a pen so he could sign the guest book at the Peace House building on the southern side of the truce village of Punmunjom (KOREA SUMMIT PRESS POOL/AFP/Getty Images)

Ms Kim and her brother's wife, Ri Sol-ju, accompanied the leader on a surprise visit to China for a summit with the country's president, Xi Jinping, last month.

It appears likely she will join Mr Kim for his next summit, with Donald Trump, in May or June.