The 29-year-old England captain appeared to be in pain after Morteza Pouraliganji brought him down with a lunging tackle three minutes into the second half on Monday.
Kane managed to stay on the pitch until the 75th minute when he was replaced by fellow striker Callum Wilson.
After the game, Kane was walking with his right ankle lightly strapped, and with a slight limp.
Gareth Southgate played down fears Kane could be set for a spell on the sidelines but the FA are assessing his injury ahead of England’s second group game on Friday.
Southgate said in the aftermath of England’s 6-2 win over Iran: “I think Harry’s fine. It looked like a bad tackle but he carried on in the game. We took him off because we felt it was a moment in the game we could do that.”
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England’s current No 9 needs three more goals to become England’s all-time record goalscorer.
He currently has 51 goals in 76 appearances for his country.
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(Photo: Liu Lu/VCG via Getty Images)