"Iborra is an injury to his hamstring," Puel told reporters ahead of Saturday's trip to seventh-placed Burnley. "He will not be available for the rest of the season."
The loss of Iborra is a further blow for the French manager as Leicester are also without midfielder Matty James who had surgery on his Achilles tendon earlier this month.
With Wilfred Ndidi suspended for the Burnley clash, Puel could ask Adrien Silva and Hamza Choudhury, who came on for Iborra in the last game, to pull the strings in midfield.
"I have confidence with Silva, of course, and the young player, Choudhury. It's a good opportunity to start the game and to play with the first team. He is a good player and he has the confidence of all his team mates," Puel said.
Leicester are eighth in the table with 43 points, six points behind Sean Dyche's Burnley. Depending on results in the FA Cup, a seventh-place finish could turn out to be a qualifying place for next season's Europa League.
(Reporting by Shrivathsa Sridhar in Bengaluru; Editing by Christian Radnedge)
