That's similar to the Icom OPC-617 cable. The Icom cable has a DB-9 on the end, so that's likely after market. If you do a search on the Icom OPC-617 cable, you will see what is available.
If you are not going to use it, you can open up the radio and unplug it.
Since that looks like the same connector thats inside the radio, it was likely connected to the other radio to make the repeater.