Mobility allowance taxed in...

Mobility allowance taxed in the UK? Hi everybody, I hold a Marie Curie IEF in the UK and I am afraid here they will tax my mobility allowance. According to the guidelines (Work programme etc.), it is apparent that the mobility allowance is an expenses contribution, not part of the salary, and it should be tax free. I held a previous Marie Curie IEF in Germany and I got the mobility allowance tax free, however I read on the website of some UK university that they apply employee's income tax and national insurance to it. Are they allowed to tax an expenses contribution? It is nonsense, and it brings my salary to the level to which it is taxed for 40% and not 20%, it makes a great difference. I read in an official Marie Curie FAQ that the mobility allowance is meant to be tax free, if local legislation allows it. My host institution has no experience about Marie Curie fellowships, I am the first one ever holding one here. Does anyone know more about the taxation of mobility allowance in the UK? From personal experience or from knowledge of UK tax law? Thanks, Maria Paola