The Bexley-born forward's switch to Tyneside over the summer was viewed as a significant coup for the Magpies, who fought off competition from Manchester United, Manchester City, Tottenham and Liverpool to land one of English football's most highly-rated teenage prospects after his contract at the Emirates expired.
Thompson had originally been on Newcastle United's radar back in 2024 before opting for Arsenal, having first come through the Gunners' Hale End academy as a young boy prior to a spell at West Ham United.
"It's been a lot of hard work towards signing my first professional contract," Thompson said. "I believe joining Newcastle was the right step towards what I want to achieve.
"I'm happy to be here and very excited for the future.
"My strengths would be dribbling, drifting inside and being able to play the ball in behind. I'm a technical player who likes to create chances and score goals for the team. A big reason why I came here was the chance to play Under-21s football and be able to train with the first team, getting pushed and exposed to senior football as quickly as possible. I feel like this is the right place to do that."
The England Under-17 international made 33 appearances for Arsenal's youth sides, scoring four goals and creating three assists, and featured in their UEFA Youth League campaign last season, netting in a 4-2 win over Bayern Munich. Since arriving at Newcastle, he has already made his debut for the club's Under-18s in a 3-2 win over Stoke City and scored his first goal in a 4-1 away victory at Leicester City, a rapid start that has coincided with the announcement of his new contract.
Thompson admitted the move has not been without its challenges, particularly being separated from his family.
"It's been hard missing my family, especially my brothers, but I think, in life, you've got to make sacrifices and believe it will all be worth it in the end," he said. "I think I'm familiar with joining a new club after moving to Arsenal from West Ham before, but I've been working really hard on and off the pitch. The coaches have helped me a lot to settle in, and I need to keep doing my thing on the pitch."
Academy director Steve Harper praised the teenager's adaptation to life at the club.
"Kyran has handled a big move at a young age exceptionally well and has made a positive impression on everyone here," Harper said. "Signing a professional contract is a big moment for him and is a reward for the standards he's set early on, and now the challenge is to keep building on that."
Thompson is one of eight academy prospects signed by Newcastle over the summer as part of a recruitment drive that has extended well beyond the first team.