Remove the skin from the fish and flake the meat into small shreds using your fingers and a fork, taking care to remove any pin bones and tough edges. Flaking the fish finely is key, so take your time.
In a medium bowl, stir the cream cheese until it is smooth. Add the labneh and stir until the mixture is smooth, using a whisk if needed. Stir in the smoked whitefish and scallions, taste, and season with a pinch of salt. Serve the dip with vegetables and crackers.