On a JAR CPL I doubt the insurers on local aviation authority would allow it.
If you have 1500hrs+ and meet FAA ATP requirements then just do the ATP written and skills test <1500hrs and you will not be able to take the ATP test, so for a second in command type rating you will need an FAA multi engine instrument rating. This will mean a trip to the US, including visa hassles and a check ride on the actual aircraft that in not a gimme by any means. I could be wrong on this but people I know with low hours have had to do it this way.