There are two possible scenarios here. Either you are above him on the organizational chart, in which case you probably have the authority to let him go.
More likely(As you're not sure what his contributions are), you are lateral to him on the chart. Possibly try to engage him in what you're working on. Maybe he's not particularly self driven and would value the guidance from someone more senior. If he turns it down, either just ignore it and move on(if it is not affecting you), or if his failure to do work impacts you directly, then complain to your manager. T
More likely(As you're not sure what his contributions are), you are lateral to him on the chart. Possibly try to engage him in what you're working on. Maybe he's not particularly self driven and would value the guidance from someone more senior. If he turns it down, either just ignore it and move on(if it is not affecting you), or if his failure to do work impacts you directly, then complain to your manager. T