Sunderland have signed France Under-20 international midfielder Pierre Ekwah from West Ham United on a "long-term" contract, for an undisclosed fee.
The 21-year-old joined West Ham's under-21 side in July 2021, having been part of the Chelsea academy, but did not make a senior appearance.
Before moving to England, Ekwah spent time at the national Clairefontaine academy and at Nantes.
"We believe he will add something different to the dynamic of our midfield.
"Having met him, he has a brilliant personality - he wants to get better and show he can play first-team football. He brings a level of physicality and we're really looking forward to working with him.