The Health Minister says there's no guarantee that construction of the new National Children's Hospital won't go over budget.

Plans for the facility on the St James' Hospital campus were lodged this afternoon.

If planning is granted building of the 650 million euro facility could begin next year.

Health Minister Leo Varadkar has expressed confidence planning will be granted.

But speaking to Matt Cooper on the Last Word this evening, he couldn't rule out cost over-runs: