What the hell is the ship in the bottom left?? Secondary Hull forward of the saucer?

bottom right? curry class. kitbash.

@grishnar Memory Alpha only identifies it as a Federation Tug:

The episode “A Time to Stand” needed a shot of a retreating flotilla of Starfleet vessels. To beef out the scene, the production staff built several new ships, kitbashing them out of parts from commercially available AMT/Ertl-Star Trek model kits. Amongst them was the Federation tug, built by Judy Elkins, and affectionately called the “USS Ertl” among the staff themselves. The warp engines were those of a D'deridex-class Romulan warbird, originating from AMTkit no. 6858. Though these ships were mentioned before in dialogue in Star Trek: The Next Generation, “A Time to Stand” marked the only on screen appearance.

Thing is the colouring of the model, general build and nacelles always made me think this isn’t a Federation but a Klingon tug instead.