Transport modelling of plasmas with internal transport barriers in JT-60U and JET tokamaks has been carried out using integrated modelling codes TOPICS and CRONOS for the prediction of high-beta steady-state scenario in JT-60SA, which shares important characteristics with both tokamaks. Typical models of anomalous heat transport, which is one of major uncertainties in the prediction, have been validated for the experimental data in JT-60U and JET, and TOPICS and CRONOS equipped with the models are used for the model verification. It is found that CDBM model predicts temperatures close to experiments or underestimates them, and thus can be used for the conservative prediction, which considers a lower bound of plasma performance. By using the CDBM model, a JT-60SA high-beta steady-state plasma has been conservatively predicted within the machine capability. The conservative prediction shows that the JT-60SA has enough capability to explore high-beta steady-state plasmas and their controllability. Model modifications related with an E × B shear effect to improve the prediction capability are discussed.