After an impressive FIFA World Cup in Brazil, the Netherlands international has been linked with a move away from the Premier League outfit.
Vlaar, 29, watched on as Villa slumped to a 4-1 loss to Groningen in a pre-season friendly on Saturday.
Lambert has already had a chat with Vlaar, but plans to have further discussions with the Dutchman.
"I had a really brief conversation with Ron. No doubt I will sit with him when we have a bit more time when we're back," he told the club's website.
"He's positive and raring to go. He's looking forward to getting going. That, it itself, is a plus.
"He loves it here. That's him back now. He's looking forward to the Stoke game."
Christian Benteke (Achilles) and Libor Kozak (leg) will miss the start of the Premier League season, while Joe Cole may do likewise.
Lambert said: "In terms of injuries, Libor is doing great. He won't be fit for the start of the season. Christian won't be fit either. But they are both ahead of their scheduled time.
"Joe is doing great. He started running again. We will see how he is next week.
"But Libor and Christian, as our long-term injuries, are doing really well."
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