Query re Responsbility for having Nest door's vehicle removed from our parking space

Other

We have a property that we have leased on a three year let. The house has a designated parking space which is situated next to another space belonging to the property next door which is also tenanted. Next door have parked a large van which straddles both spaces. It transpires that the van is stationary and they are using it as a storage facility. The rubbish that has built up round the van has brought it to the attention of Environmental Health who contacted us about it. Subsequent Investigations by Environmental Health confirmed that it belonged to the tenants next door.

The tenants next door are currently refusing to move the vehicle. It’s removal would be as I understand it, a civil matter. My question is would it be my responsibility to escalate this issue to a civil court or would it be the responsibility of the body which we have leased it to, to return the property to us at the end of the lease, with the parking space vacant as it was when we provided the property at the outset of the tenancy.

Many thanks & regards.