Route Objects which RIR to use?


Hi

I'm looking for some guidance. If a customers address space is registered in 
another RIR like ARIN and we are announcing it from a ASN registered in RIPE or 
visa-versa where should we create the route object in ARIN or RIPE. If in RIPE 
is there any authorization hierarchy for doing this, I suspect not?

Regards
Paul