The hospital is being constructed by Kill-based developer BAM.
It could be 2027 before the new National Children's Hospital is open to the public, according to Sinn Féin.
It comes after another reported delay to the delivery date of the hospital, from June to September of this year.
A commissioning process to fit out the hospital will then follow, which could take some time.
The hospital is being constructed by Kill-based developer BAM.
After speaking with BAM in February, Health Minister Jennifer Carroll MacNeill said the build on the new National Children's Hospital was 98 or 99 per cent complete.
Now reports suggest a delay of the completion date from June to September this year.
That delay is expected to be confirmed at an Oireachtas Committee hearing this week.
It's led to calls from Chair of the Health Committee, Padraig Rice, for the Health Minister to appear before the Dáil.
After completion there will be a lengthy fit-out process commenced.
Sinn Féin's Health Spokesman David Cullinane says the opening date is impossible to predict.

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