"I'm really happy because I'm here to play football," Lee said at the National Football Center in Paju, north of Seoul. "Since I'm training with the players who are older than me, I will try to learn many things before going back to Spain."

Lee has been considered one of the future stars by football fans here. He first gained public attention through a local television show for young footballers in 2007 before joining the Spanish club in 2011.

After showing exceptional performances for his age level, Spanish media have been reporting that Lee is linked with a move to Real Madrid or Manchester City, but he recently signed a contract that will keep him with Valencia until June 2019.

"I'm happy that I'm learning football in Spain, which people call one of the best football nations in the world," he said. "I enjoy living there and learning football. I want to say thank you to people who told me I've got good skills."

Lee is one of the South Korean football starlets in Spain, along with FC Barcelona's Lee Seung-woo and Paik Seung-ho. Both Lee Seung-woo and Paik play for the U-20 national team currently gearing up for the FIFA U-20 World Cup this month at home.

"Lee Seung-woo is a famous player in Spain and he is really a good footballer," he said. "I hope they can earn good results at the U-20 World Cup."

Lee said he dreams of playing for the South Korean senior national team in the future.

"I'm Korean and I want to become a national team member," he said. "I will work hard in Spain and will try to become a player who can lead South Korean football in the future."

Head coach Chung said he also has big expectations for Lee.

Chung's side is preparing for the qualification of the 2018 Asian Football Confederation U-19 Championship, with sights on the 2019 FIFA U-20 World Cup.

"Lee is on the first page of his national team career," Chung said. "Before training, I told him to make good memories during his stay here and not be bothered by the surrounding environment."

The 48-year-old coach said he believes Lee will give some positive energy to the team as the young footballer has more international experience than other players on the squad. 

"I have only seen him through video until now, but Lee is a good player," he said. "I will figure out his style through training." (Yonhap)