As far I know and understand the Intel Warranty coverage for NUC, this product is covered by three years of international warranty. You should ensure to buy this NUC from Intel Authorized Dealer and keep the prove of purchase and the box with all S/N as well. I believe that in short time you will got an confirmation from Intel Agent.
You can also try using the chat service (http://intelsupportchat.force.com/icslivechat/ics_tech_desktop_ww_english_Chat), this is English-only and is subject to office hours (9-5 M-F) in the Pacific (UTC-8) time zone.
Raju is wrong! He should have actually read the documents before posting links to them. Unfortunately, posting useless, misleading and often completely wrong information seems to be his thing.
The NUC products have an international warranty. You are covered regardless of where you purchase your NUC.