The present disclosure relates to an improved process for the preparation of a sulfonamide structured kinase inhibitor, namely N-(2′,4′-difluoro-5-(5-(1-methyl-1H-pyrazol-4-yl)-1H-benzo[d]imidazol-1-yl)-[1,1′-biphenyl]-3-yl)cyclopropanesulfonamide (1A) and pharmaceutically acceptable salts thereof. Compound of formula (1A) is a selective inhibitor of FGFR/VEGFR kinase families and is useful in the treatment of cancer.