Bus Éireann tonight issued a statement saying ABS is fitted to some buses and is operational on those in service.
The company had earlier declined to comment on claims that the anti-lock braking system on school buses is frequently disabled or switched off.
Safety experts are investigating the claims.
The issue arose as part of the investigation into the fatal Navan bus crash earlier this year. Five schoolgirls were killed in the collision.
It is understood the Health and Safety Authority and the garda are investigating why the ABS system is not used on many school buses.
