OP, this is almost impossible considering the fact that this currency is decentralized, just to think of it, his many countries in the world are ready to adopt Bitcoin, before you talk about reserve there should be interest, and know that we understand what interest is all about, the government assume that Bitcoin is an enemy of individual country currency, so making it reserve will amount to more depreciation of existing currencies and at so doing bitcoin will become more valuable more than how it is presently, we just have to be sincere this process will be very difficult to come in place because of the circumstances surrounding the acceptance of Bitcoin as a legal tender worldwide.