Leicester have signed Monaco midfielder Youri Tielemans on loan until the end of the season in a deal that sees Adrien Silva go the other way.
Tielemans, 21, has scored five goals in 20 appearances in Ligue 1 this season having joined Monaco from Anderlecht in 2017.
The highly rated Belgium international has 14 caps for his country and played at the 2018 World Cup.
"I'm really excited to get going," Tielemans said.
"The Premier League is one of the best leagues in the world and when I was young, I always watched Premier League games. I'm really happy to be here and I'm excited to get started.
"It's a big family. Everybody is really kind and really good with me. I think it will be really good here."
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Who is Tielemans?
Tielemans is the youngest Belgian to ever play in the Champions League, aged 16 years and 148 days when he featured for Anderlecht.
He found the net roughly once every six games for Anderlecht - winning the league title twice - during four seasons and eventually moved for around £22m.
He has started 20 of Monaco's 22 league games this season and scored five league goals but the French side has struggled, leading to the sacking of Thierry Henry.
Only Radamel Falcao - on eight - has scored more goals for Monaco this season and Tielemans has also created 19 chances in his 20 league games.
Silva's problematic Foxes stay over?
Silva has failed to make much of an impact at the King Power Stadium since arriving from Sporting Lisbon for £22m in 2017.
He was forced to wait six months to make his debut after the paperwork arrived with Fifa 14 seconds late and has never really recovered his form, making just two Premier League appearances this season.
The Portugal international is highly rated by new Monaco coach Leonardo Jardim.
BBC Radio 5 live reporter John Bennett
Youri Tielemans has always been tipped for big things. At the age of just 16 he made 29 appearances in his first season at Anderlecht and continued to impress in the following campaigns, making his international debut at 19 and winning Belgian footballer of the year prize after his final season in the country's top flight.
It came as a surprise when things didn't work out at Monaco last season - head coach Leonardo Jardim never seemed to trust Tielemans and he spent a lot of time on the bench.
Despite Monaco's terrible form, things improved for him personally when Thierry Henry came in but Jardim's return was probably the last thing he would have wanted.
Now, it's a chance to get his career going again and, at 21, there's plenty of time. Tielemans has got a great range of passing, he can make driving runs forward and having starting his career as a more defensive midfielder he can help to keep things tight at the back. All in all, that makes him the perfect partner for Wilfred Ndidi in the Leicester midfield.
It's a loan move that suits Leicester, suits Tielemans and suits Monaco; they know that if he plays well at the King Power Stadium they'll be even more interest for a big money permanent transfer in the summer.