Fresh doubts are being cast over progress on the new National Children's Hospital after the latest in a line of setbacks for the project.

Earlier this week it was revealed that the project may be held up due to a sewer running under the site at St James's Hospital in Dublin.

It's thought that rerouting the sewer could add €18m to the cost of the project and significantly delay building work.

The hospital's board says it won't have any impact and the hospital is "comfortably" on schedule.

However, the Irish Times Health Correspondent Paul Cullen says he doubts the project will meet its 2018 deadline: