The two Frenchmen have been training at the club's London Colney base over the past week, leading to speculation that they could be re-signed by Wenger on playing contracts.
However, the Arsenal boss clarified the situation in his Monday press conference ahead of Tuesday's visit of Marseille in the Champions League.
Wenger said: “They like to come back to Arsenal, to practise. When they can join in, they do. They integrate well with the spirit of the team. Nothing more than that!
“They have no real target to bring something, they just want to enjoy themselves and keep their fitness. Usually they don’t practise with the first team because they come in and work on fitness.
“It is a little bit less competitive, [but] when we have some room we invite them to play with us but usually they train separately to us.”
Henry is fresh from a successful season with the New York Red Bulls, where he helped his side win the Eastern Conference and finish top of the MLS standings before losing to Houston Dynamo in the Conference semi-finals, while the 40-year-old Pires has been a free agent since departing Aston Villa in May 2011.
Discussing a potential future role at the club for Henry - who has already made one loan return to Arsenal since leaving the club in 2007 - Wenger added: "No, at the moment he is invited just to practise when he wants.
“We have a big staff, a very competent one, and we have the right number to support the team to achieve the targets.
“Thierry is a player, one day certainly it will be different, but at the moment, no.”