The presently claimed invention relates to a process for preparing urea urethane polymer, liquid compositions comprising the urea urethane polymer and the use of the urea urethane polymer as a thickening and thixotropic agent for water based and solvent based paint and coating formulations, lacquer, varnish, paper coating, wood coating, adhesive, ink, cosmetic formulation, detergent formulation, textile and drilling muds plaster formulations, PVC plastisol and cement formulations.