It has been widely reported that the Glasgow giants are interested in bringing Van Dijk to Glasgow, with the player's agent Martin Henk Chin stating: "It is true that a bid for Virgil has been made but I can't say anything about the club."
In addition to this, Groningen director Hans Nijland also admitted that there was an offer on the table for the defender, but again did not reveal the club.
Celtic are rumoured to have already made two bids for the tall, imposing defender, and it may be that the current approach is the Scottish champions trying to finally land their man.
There has also been interest from within the Eredivisie, with Ajax, PSV and FC Twente all rumoured to be looking at the player, but Nijland confirmed that the move had come from outside the Netherlands.
"There is a bid from a foreign side," Nijland told magazine Voetbal International.
"The offer and our valuation are not on the same line at the moment. We want to keep Virgil but we understand his ambitions. It's an exciting period."
Van Dijk played every league game for Groningen last season as the club finished seventh in the Eredivisie.