You must prove your proficiency in English by submitting the results of one of the following tests:
IELTS Academic: minimum total score of 6.5 and a minimum subscore of 6.0 on the Writing and Speaking sections  of the test.  

We do not accept IELTS Online.  
TOEFL iBT: minimum total score of 90 and minimum subscores of 21 for Speaking and 22 for Writing for TOEFL iBT: Computer based and/or Paper Edition, at a test center.  

We only accept TOEFL iBT Home Edition scores in exceptional circumstances, such as when on-site language test centers are closed or inaccessible due to unsafe conditions in a country.  
Cambridge C1 Advanced or C2 Proficiency: minimum total score of 176 and a minimum subscore of 169 for Writing and Speaking.  

The minimum required Cambridge level is below the official Cambridge Advanced pass mark, but is in line with comparable tests and therefore accepted for admission.
Please note  

The test results must be no older than two years prior to the start of the academic year
We only accept scores from a single test date. Combinations of scores from multiple test dates, such as TOEFL MyBestScores and IELTS 1 skill retake, are not accepted.
You must be able to demonstrate your English language proficiency at the time of application. Without test results your application cannot be processed unless you are exempted. Please keep in mind that it may take 1-2 weeks to receive your results after you take the test. 
An English proficiency test is not required if the following applies to your situation:  
You completed your entire Bachelor's or Master's program in one of the following countries:  
Australia, Canada (with the exception of Quebec), Ireland, New Zealand, the United Kingdom, or the United States of America.  
For all other countries and situations, the English language test is mandatory.  

For test information and registration details, including applicable fees, please visit the official websites of IELTS, TOEFL, and Cambridge.