The invention describes a thermal block assembly comprising a first thermally and electrically conductive block part realised for connection to an anode pad of a light-emitting diode (LED) and dimensioned to provide an essentially complete thermal path for heat originating at the anode pad; a second thermally and electrically conductive block part realised for connection to a cathode pad of the LED and dimensioned to provide an essentially complete thermal path for heat originating at the cathode pad; and a bonding layer applied to the block parts to fix the positions of the block parts on either side of a gap. The invention further describes an LED arrangement comprising said thermal block assembly and at least one LED mounted thereto, and a method of manufacturing said thermal block assembly.