A pressure sensing assembly (1), comprising: an elongate, axially extending tube (100), having a flexible tube wall (102) that encloses an inner pressure chamber (106); and at least one sensor unit (200), including: two tube wall fixation devices (210), connected to the tube wall (102) at respective axially spaced apart positions, and configured to fix respective diameters (D, d) of the tube wall at said positions; and a first strain sensing element (220), connected to the tube wall (102) at a first position axially in between said two tube wall devices (210), and configured to provide a first signal indicative of an axial elongation of the tube wall resulting from a change in axial curvature of the tube wall when a pressure differential between the inner pressure chamber (106) and an outside environment (108) of the tube is applied across the tube wall at said first position.