In the traffic rules it is stated that a driver must be able to stop within the distance which they can see is clear and before reaching any foreseeable obstruction.

Additionally, there is a special provision stating that drivers are obliged in particular to maintain sufficiently low speed so that they can, if necessary, stop when passing children on or near the road.

You must therefore both reduce your speed and change your position so that you may safely pass the children playing by the road.