Valencia announced the signing of Francis Coquelin from Arsenal.
The midfielder has signed a four-and-a-half-year contract at Mestalla, which includes an €80million release clause.
Valencia is reported to have paid in the region of €13.5m for the 26 year-old.
"Valencia have this Thursday reached an agreement with Arsenal for the transfer of Francis Coquelin," A Valencia statement confirmed.
Arsenal manager Arsene Wenger revealed that a deal was likely to be concluded, with Coquelin having grown frustrated by his lack of game time.
"He goes to Valencia, he didn't get enough games," Wenger said following his side's 0-0 EFL Cup semi-final draw with Chelsea.
"I let him go."
Coquelin has only made one start in the Premier League this season.