A 62-year-old man with known chronic kidney disease (CKD) stage 4 (eGFR 25 mL/min/1.73m²) presents with fatigue. Blood tests show: Hb 95 g/L, MCV 85 fL. Iron studies show: Ferritin 50 µg/L, Transferrin saturation 15%. What is the most appropriate initial management for his anaemia?