Manager Mauricio Pellegrino has chosen a panel of 25 players to head for Evian-les-Bains, but the Netherlands international centre-back will not travel with the team as speculation grows that he could make a switch to Arsenal or Liverpool in the coming weeks.
Southampton have been fighting to retain the services of the 26-year-old former Celtic centre-back, stating in June that he is not for sale "at any price" and even threatening legal action after indicating they felt Liverpool had made an illegal approach for him.
For a period, that quelled the Reds' apparent interest, yet over the course of the last fortnight, reports have steadily increased linking the Anfield club with a renewed push to sign the defender.
On July 21, Pellegrino confirmed that Van Dijk had asked to leave the club and said that as a result he would have to train alone.
Arsenal have also been associated with a move for the Dutch defender, who has played 55 times in the Premier League since moving to the Saints in 2015.