The 21-year-old is expected to leave the Gunners on loan until the end of the season.
The Mirror reports that Valencia vice-president Javier Gomez and sporting director Braulio Vazquez have flown into London for talks about signing a loan deal for Vela.
Arsenal boss Arsene Wenger is reportedly keen for Vela to join another Premier League club on loan and the forward has long been linked with a move to Bolton.
His agent, Eduardo Hernandez, told a Spanish newspaper: “Nothing has been decided. I’m going to London this week to resolve the case. We will explore all options available to him, and when I say all I mean everything.
“Carlos has good memories of Spanish football and it’s flattering that a club like Valencia is interested. We will analyse the situation.”