Arsène Wenger has indicated that Abou Diaby, whose contract runs out at the end of the season, could be offered a new deal by Arsenal despite his fitness problems.

Diaby, who played 45 minutes in a practice game on Tuesday, broke an ankle against Sunderland in 2006 and he has struggled with injuries ever since, making only 22 appearances in the past four seasons.

The French midfielder has featured once competitively this season, playing for 67 minutes in the Capital One Cup defeat by Southampton in September, but Wenger suggested there is a chance Diaby could remain at Arsenal if the right deal can be agreed. However, he cautioned that Diaby will have to prove his fitness over a sustained period.

“I had a chat with him and told him how I can envisage the future,” Wenger said. “He has to make a decision. Of course he understands completely that he has to perform and to show that he can be present on a consistent way.

“I will see where we go from there. I wouldn’t like to go into details, we have to meet again to see where we go from what I told him. It has to be linked a little bit with his presence.”

Wenger, who said Mathieu Debuchy and Jack Wilshere could be involved against Liverpool on Saturday after returning to training this week, refused to take questions on the future of Raheem Sterling. Arsenal have been linked with a summer move for Sterling, who is yet to sign a new contract with Liverpool.

“I don’t want to interfere in that, especially 48 hours before the game,” Wenger said. ”That’s down to Liverpool, I don’t want to interfere in that. It’s not my problem.”

Video: Arsène Wenger refuses to discuss speculation over a possible deal for Liverpool’s Raheem Sterling. Guardian

Wenger also questioned proposals by the Football Association’s chairman, Greg Dyke, to increase the number of homegrown players in squads from eight to 12.

“I believe we are in a top-level competition and you earn your right through the quality of your performance rather than your place of birth,” Wenger said. “Secondly, I’m happy to, and would like to contribute to the quality of the English national team, but you have two questions you can raise before that. What is the heart of the problem?

“First of all between 1966 and 96 there were no foreign players in England and it didn’t improve too much the performances of the national team. Secondly, if between the ages of 16 and 21 the youth teams in England win every single competition in Europe then you could say yes, there is something that we have to do because they are not getting their chance at the top level. That is not the case, on the contrary. I think between 16 and 21 the English youth teams, until now, have not performed.

“So that’s the heart of the problem. Let’s get better at that level, then if there is a problem integrating these players in the top teams, we have to do something about it. I think today you have to be very brave to integrate the young players in the top teams because the pressure is very high. I still believe when the players are good enough, they play.

“You speak about Sterling and [Harry] Kane. Nobody stops the quality, no matter where they are from. So let’s focus on that first. Apart from that I support every single measure that improves the English national team but it has to be efficient. Sometimes what looks a good solution is not necessarily the right one.”