Here's a couple of extracts from their warranty terms and conditions - it basically says they may honour the warranty or they might not, depending on whether you've registered the device properly etc.
Apple may restrict service to the country where Apple or its Authorized Distributors originally
sold the hardware product.
You may be responsible
for shipping and handling charges if the product cannot be serviced in the country in which
service is requested. If you seek service in a country that is not the country of original purchase,
you will comply with all applicable import and export laws and regulations and be responsible for
all custom duties, V.A.T. and other associated taxes and charges. Where international service is
available, Apple may repair or exchange defective products and parts with comparable products
and parts that comply with local standards. In accordance with applicable law, Apple may require
that you furnish proof of purchase details and/or comply with registration requirements before
receiving warranty service.