The 22-year-old was on the sidelines for the opening five months of this season after undergoing shoulder surgery, returning in December.
But he picked up an ankle problem during Leinster’s 38-7 win over Ulster on Saturday and was forced off in the second half.
He has been diagnosed with “syndesmosis of the ankle”, according to the Six Nations’ official website, which carries a recovery period of approximately six weeks.
Ringrose started all five Six Nations matches last year, and has four tries from 11 appearances overall.
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