Why do you need IELTS ?
Universities in western countries has to ensure the candidate they provide admission for the courses at their educational institute, should have the ability to understand English during the lectures as all the Professors and tutors will be from native English speaking countries and eventually they lectures will be in English alone; in addition to that, they also should be capable of having good writing skills in English language as there will be many assignments which are to be submitted along with some thesis and dissertation while they submit their project.