Houllier said:"Steven's injury problems are all behind him now, and he no longer goes to Paris for treatment. But with Liverpool facing 10 games in 30 days I think Sven will take that into account.
"I will not stop him going, and you cannot have an agreement about how long he plays for, but you rely on the national coach being sensible.
"The target for Sven is to get his players at their best for the end of March when they face a double-header against Liechtenstein and Turkey - that's what matters."