Yes - Deconfliction service available under both VFR and IFR.
Controllers can apply a Deconfliction Service below the radar safety altitudes to aircraft on climb-out and approach but will only give vectors to assist with collision avoidance (not separation) along with a terrain warning.
The duty of care has been clarified - pilots are emphatically responsible for collision avoidance and terrain separation at all times. Controllers may assist with separation (Deconfliction Service) or Situational Awareness (Trafic Service/Basic service) and may assist with collision avoidance under any service.
No instructions are mandatory. Class G airspace safety is underpinned by 'see and avoid' principle as applied to the pilot, not the controller.