Just days after manager Rafa Benitez quit for Dalian Yifang, Perez was sold to Leicester for £30m.
“Newcastle made my dreams come true – to be able to play in the Premier League," he said.
“It's been five years, a lot of experiences and growth as well.
“I am happy to be able to keep playing in the Premier League for such a great club as Leicester. I'm very proud to be here.
“They are big players and I can't wait to start playing next to them, and know them as well. I can't wait to start training and getting to know them.
“Those kinds of trips [to Evian] are very important for new signings and for new players.
“It is going to be great for myself to get to know my team-mates, to train as well. It is going to be a great week, a lot of hard work as well, but the most important thing is to get to know my team-mates."