The Paris Saint-Germain star said on Tuesday he will be well rested when soccer's showcase tournament begins on June 14.
Neymar told journalists during an event for one of his sponsors: "I will have enough time to arrive in Russia in good shape."
The 26-year-old also said he will have his last medical exam on May 17, and could be available for Brazil's training sessions that start May 21 near Rio de Janeiro.
Neymar striker had surgery in March on a cracked fifth metatarsal in his right foot.
The Brazilian also said it was hard not to be with his PSG teammates to celebrate their French league title on Sunday.
PSG thrashed 2017-18 champions Monaco at the Parc des Princes to confirm the title in Unai Emery's second season in charge, although speculation remain over the coach's future after another year of disappointment in the Champions League as they fell at the last-16 stage to Real Madrid.
Additional reporting by the Associated Press.
