Atletico Madrid striker Costa is currently nursing a hamstring injury having suffered a setback in his recovery just minutes into his side's Champions League final defeat to Real Madrid last week.
Suarez underwent knee surgery in Uruguay last week, while Colombia star Falcao has been injured for the majority of the season, and the former Los Blancos defender thinks that their omission would harm the tournament.
"The loss of a player like Luis Suarez, Diego Costa or Radamel Falcao would be decisive," he told AS
"They're very important for their national teams and I wish they were all there. It would be good for the competition. Strikers are artists whose goals decide matches."
The World Cup kicks off in a fortnight, with hosts Brazil playing Croatia in the opening game.