Its the skill test that needs to be undertaken in the JAA state of issue or in the case of the UK at overseas schools which have approval such as Jerez in Spain. There are a number of UK FTO's that use a US school to undertake the bulk of the training to keep costs down (read increase profits) and then the student comes back to the UK and does about 10 hours or so to finish off prior to taking the test. Invariably these schemes involve doing an FAA IR and then converting it to JAA in the UK.