Croatia face Portugal in the round of 32 on Thursday night after finishing second in Group L following a 2-1 win over Ghana.
Zlatko Dalic's side will go into the tie as underdogs, and Vuskovic's full focus remains on helping Croatia through to the next round before his club future is addressed.
The 19-year-old, who has yet to make a competitive appearance for Spurs, wants to leave the club this summer to secure first-team minutes elsewhere.
He is prepared to submit a formal transfer request to force through a move and has attracted interest from Brighton as well as a number of top European clubs.
Brighton have already had at least two bids rejected for the teenager, who spent last season on loan at Hamburg in the Bundesliga and earned a place in Croatia's World Cup squad on the back of that form.
He started Croatia's opening group game, a 4-2 defeat to England, but has been named on the bench in each of their last two matches against Panama and Ghana.
Vuskovic is regarded as one of the brightest young defenders in Europe, but talks with Tottenham manager Roberto De Zerbi made clear that consistent first-team minutes would not be available.
Spurs have signed centre-backs Marcos Senesi and Jan Paul van Hecke this summer, with De Zerbi prioritising experience and leadership at the back. Asked about his future before the tournament began, Vuskovic was clear about what he needed from the next step in his career.
"For now, I'm focused only on the World Cup," he said. "My goal next season is to play for a club that wants me and where I will play. We'll see what happens in the coming days and weeks."