Wilshere is one of several players at the club whose contracts are due to expire at the end of the season, leading to intense speculation over his future.
The England international went out on loan to Bournemouth last season in a bid to prove his fitness and win back a place in the Arsenal team, but he has played just 48 minutes of Premier League football this season, all from the bench.
Wilshere has been ravaged by injuries over the last three years, but he is fit ahead of Arsenal’s meeting with Huddersfield Town on Wednesday.
And Wenger says that remaining fit – rather than earning a new contract – is what the 25-year-old should be concentrating on at the moment.
“For him, it’s just about being fit and considered like any other player in the squad,” Wenger told reporters at his pre-match news conference.
“He’s at that level now where every opportunity is a good chance for him to commit to his long-term future.
“I don’t think about the long term. For him I always consider his interest because he’s an Arsenal player since he was a kid and I think about what’s best for him, regardless of the decision I make.
“If I think it right and in his best interests for him to stay here, then I fight 100 per cent for him to stay because he’s a top-quality guy and is back fit now.
“When you have a top-quality player you want them to stay.”
It was also put to Wenger that he has substituted Alexandre Lacazette 10 times in the Premier League this season, but the manager insisted there is nothing untoward behind that statistic.
He said: “First of all, I’d like to say that you sub strikers more than defenders because they have to create, provoke and be incisive.
“But I think he has adapted physically to the Premier League and I am very happy with him.
“Physically, the Premier League is very demanding and demands a lot of work. If you look at other teams they also change strikers after 70 or 80 minutes.
“Sometimes they [strikers] work on their own against two or three people. In attack you provoke, and at the back to respond, and that [provoking] is more difficult, more demanding.”