Usage control model (UCON) is one of the emerging and comprehensive attribute based access control model that has the ability of monitoring the continuous updates in a system making it better than the other models of access control. UCON is suitable for the distributed environment of grid and cloud computing platforms however the proper formulation of this model does not exist in literature in any policy specification standard. It is for this reason that UCON is not widely adopted as an access control model by industry, though research community is now paying attention to make standard policy specification for this model. In this paper we are suggesting the interpretation of UCON model in extensible access control markup language (XACML) which is an OASIS standard of access control policies. We also highlight UCON model features by explaining its core processes and characteristics with respect to the case study of financial application.