The Lyon forward has scored 27 goals in 33 top-flight appearances this season as he helped the Ligue 1 side challenge Paris Saint-Germain for the title.
So if he looks after himself and if he does the right thing then he can become really top notch
Lacazette has been linked with a big-money move to the Premier League amid reported interest from Arsenal and Liverpool.
And Houllier, who managed Liverpool for six seasons before he was sacked in 2004, talked up Lacazette’s talent in an interview with Ligue 1’s website.
“He’s top of the premier league in France, the Ligue 1, but he’s not international yet, and he knows that. But he can be world class,” Houllier said.
“I was told he’s a very dedicated professional. So if he looks after himself and if he does the right thing then he can become really top notch.”
Lacazette has enjoyed his best season at Lyon since making his debut in the 2009/10 campaign.
The France international has scored 42 goals in 67 Ligue 1 appearances in the past two seasons.
The Lyon star received his first France cap on 5 June in a 1-0 defeat by Uruguay in a friendly in Montevideo.
Lacazette scored his first international goal in a 2-0 victory over Denmark in Saint-Etienne in March 2015.
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