The South Korea international joined Spurs from Bayer Leverkusen in 2015 and has scored 173 goals in 454 appearances.

He was captain when Tottenham beat Manchester United in the Europa League final in May to clinch their first trophy in 17 years.

The 33-year-old, who is under contract with Spurs until 2026, is in advanced negotiations with Major League Soccer side Los Angeles FC.

Son described the decision as “the most difficult one I have made in my career” as he spoke to media alongside new manager Thomas Frank.

“I came to north London as a kid – a very young age, a young boy came to London who even didn’t speak English,” Son said.

“Leaving this club as a grown man is a very, very proud moment.”

Tottenham are in Seoul as part of their pre-season preparations, with Son set to start and skipper the side against Newcastle in their friendly on Sunday – meaning his final appearance for the club could come in his home country.

Frank, who replaced Ange Postecoglou as head coach in June, described Son as “a true Spurs legend” and “one of the greatest players to play in the Premier League”.

“If that is the last game for Sonny, what a place to do it here in front of his home fans,” Frank said.

“It could be a beautiful ending.”

Tottenham also face Paris St-Germain in the Uefa Super Cup on 13 August, but Son may depart by then.

‘I need new environment to push myself’

Son said winning a title in Europe with Spurs “felt like I had achieved everything I possibly could”.

He made his Tottenham debut in September 2015 and went on to make 333 Premier League appearances.

He scored 127 times in the league – level with former Chelsea striker Jimmy Floyd Hasselbaink at 16th in the league’s all-time scorers list, above the likes of Dwight Yorke, Steven Gerrard and Ian Wright.

Son formed a memorable attacking partnership with Harry Kane, now at Bayern Munich, and the pair hold the record for the most goal combinations in the Premier League.

The pair registered a record 47 combinations, Son scoring 24 goals to Kane’s 23. In a prolific two-season period – 2020-21 and 2021-22 – they linked up 21 times for goals.

Son became the first Asian player to win the Premier League golden boot, sharing the title with Liverpool’s Mohamed Salah with 23 goals in the 2021-22 season, and a year later was the first from the continent to reach 100 Premier League goals.

He featured in the Champions League final against Liverpool in 2019 – which the Reds won 2-0 – and took over as club captain from Hugo Lloris in August 2023.

“I need a new environment to push myself. I need a little bit of change – 10 years is a long time,” Son added.

“I spent a lot of time reflecting on whether I wanted to experience football in a different environment, and I had those conversations with myself over and over again.”

Son also provided 101 assists in all competitions and holds Spurs’ record for Premier League assists with 71.

He has also made the sixth-most appearances in the history of the club – behind only Cyril Knowles, Pat Jennings, Gary Mabbutt, Steve Perryman and Glenn Hoddle.

The 32-year-old joined Spurs from Bayer Leverkusen in 2015 and has scored 169 goals in 431 appearances for the club.

The South Korea international has 125 goals and 68 assists in 320 Premier League outings.

“Brilliant,” said Tottenham boss Ange Postecoglou. “He’s already had an outstanding career at this football club.

“He’s played a big role in the last sort of 10 years, made an impact at the club and in the Premier League. It’s great to extend his stay.

“The ambition is to make sure he finishes his Tottenham career with some silverware.”

Son was part of a Tottenham side that reached the club’s first Champions League final in 2019, which Spurs lost to Liverpool, but he is yet to win a trophy with the club.

The north London side have made the announcement about his contract extension prior to the first leg of their Carabao Cup semi-final at home to Liverpool on Wednesday.

Spurs are 12th in the Premier League this season, with Son scoring five goals and registering six assists in 17 top-flight appearances.

Ange Postecoglou’s men deservedly took an early lead at home to West Ham on Thursday night but were ultimately beaten 2-1 following a second-half comeback.

No team has dropped more points from winning positions in the Premier League this season than Tottenham, who have relinquished 16.

And Spurs’ run of five matches without a win has caused the Lilywhites to drop from first, with a five-point lead at the top of the table, to fifth.

“[Whether we] deserved better or not means nothing – we lost the game. It is unacceptable,” Son told Amazon Prime.

“As players [we] should take responsibility. Attacking players should [especially] feel responsibility because we had chances to kill the game.”

Tottenham hit the post through Giovani Lo Celso’s deflected cross in the first half, while Richarlison had a fine chance to restore the hosts’ lead in the second period but nodded a close-ranger header wide.

Ultimately, though, West Ham were clinical and Tottenham lacked a ruthless touch despite racking up 23 shots.

“If you dominate a game of football you have to turn it into something meaningful and we didn’t,” Postecoglou added on BBC Match of the Day.

“We let ourselves down when we should have won the games [we have taken the lead in] comfortably.”

Tottenham made a brilliant start to the Premier League season, winning eight of their first 10 matches.

But they last tasted victory in October and have now lost three consecutive league home fixtures for the first time since September 2008, when they were managed by Juande Ramos.

After defeats by Chelsea, Wolves, Aston Villa and West Ham – all having taken the lead – talk of a title push is turning into worries of another finish outside the top four.

“The challenges are there. It is no good feeling sorry for ourselves,” said Postecoglou. “We still have a long way to go as a team and today shows that.

“In a game of football if you don’t put those chances away teams are always going to have the opportunity to punish you. In both boxes we were nowhere near where we need to be.”

Tottenham face Newcastle in the Premier League in their next match on Sunday.

The incident is alleged to have happened when the South Korean international went to take a corner in the second half of Sunday’s 2-2 draw in the Premier League.

In a statement earlier this week, the west London club said discriminatory behaviour was “totally abhorrent”.

It added at the time: “Chelsea FC has consistently made its zero tolerance position on discriminatory behaviour very clear, yet there are still idiots like this that attach themselves to this club as so called ‘fans’, which shames Chelsea FC, our coaches, players, staff and our true supporters.

“It has no place at Chelsea or in any of our communities.”

Chelsea’s long-running ‘No To Hate’ campaign launched its latest initiative on Sunday, which gives instructions on the back of every seat on how supporters can report alleged abuses either by text or by barcode on a smartphone.

They believe that identifying a specific seat from which incidents either happen or are reported will help increase the chances of individuals being caught.

The club have previously banned fans for life following racist incidents.