Heard on LiveATC that ATC wants to "cancel" something. What did the ATC mean by that? Just heard this on LiveATC:


ATC has cleared the pilot for an ILS approach
ATC then said something to the pilot, to which the pilot replied, "Roger, will cancel with you on the ground, call sign."


What did ATC say to the pilot? What are they cancelling? I didn't catch what ATC said because the audio quality was pretty bad.

The only possible "cancellation" I can think of is the flight plan, but I don't see why they would want to cancel the flight plan if the aircraft has already landed at the destination airport. Any thoughts will be appreciated.
If the airport is non-towered, then ATC may not be able to have radio contact with the aircraft after landing. However, the flight plan still needs to be cancelled or closed after landing. Usually this is done by the pilot calling ATC on the phone, but in this case it seems ATC offered to do it without the call.

Without closing the flight plan within approximately 30 minutes after the scheduled arrival time, the Flight Services will start looking for you. They will try to contact you by phone call and if that goes unanswered, eventually a search and rescue will be started. 

On ATC controlled airports the flight plan will automatically be closed after the aircraft landed.