The demand for various rare earth elements (REEs) has grown due to their significant role in electronic devices, manufacturing, medical science, renewable energies, etc. This has led to numerous studies investigating the processing of REEs-bearing tailings as secondary sources of REEs. In this study, a weathered carbonatite flotation tailing sample from an australian mine was examined. The tailing contained about 8.4 per cent total REOT and 48.3 per cent Fe2O3 where the REEs were present as REE-phosphates and the main gangue mineral goethite. Pretreatment prior to leaching the REEs was conducted through high-temperature roasting with sodium salts to convert the REE-phosphates into REE-oxides. Two sodium salts were investigated in this study; Na2COs (roasted at 900-1100C) and NaOH (roasted at 400-700℃) with different proportions added to the tailing. after Na2CO3 roasting, the iron was mostly in the form of magnetite (dominant) and hematite, whereas after NaOH roasting, most of the iron was converted into NaFeO2. In both, the phosphorous was mostly present as Na3PO4. The roasted samples were then leached with water at 65C to remove mainly the Na:PO4 phase and other water-soluble phases. The solid residue after water leaching was then leached with a deep eutectic solvent (DES) composed of an ethylene glycol-maleic acid mixture (EG-Ma) at 70C for six hrs. In general, a higher dissolution of REEs after DES leaching was achieved in the NaOH-roasted samples compared to the Na2CO3-roasted samples. However, REE extractions were modest and selectivity with respect to gangue elements was below target. The highest leaching of REEs was observed in the sample roasted with NaOH at 400°C with La (49.8 per cent extraction), Ce (3.27 per cent), Pr (44.7 per cent), Nd (31.6 per cent), Sm (30.1 per cent), Eu (34.1 per cent), Gd (30.9 per cent), Dy (42.5 per cent), Sc (70.68 per cent), and Y (69.42 per cent). The results are discussed with a view to optimising the leaching performance.