How to set AWS EBS Volume Snapshot deletion Policy?

Few of my critical EBS Volumes are being backed up as snapshots periodically. Is there any way I can setup a deletion policy by which ONLY the recent two snapshots are maintained?

For example: In one of the environment I have close to 300 snapshots from 10 EBS Volumes. Once I have this policy it should come down to 20 Snapshot and be maintained at that level.