regarding foreign property

[bisap]

Me and my wife are naturalized US citizens. We do have property in our country of Birth, i.e. Nepal. This property was there well before we were citizens. Nepal does not allow dual citizenship yet, but current constitution does allow property ownership as NRN. It has not been implemented yet, as constitution is fairly new. What will happen to this property now. Will it be lost eventually. Or can we legally sell the property. Once we became US citizen, my understanding is we gave up citizenship of country of birth.
What is the legal way that we can still retain that property or at least sell legally. Please advise or please direct us who is the best person to talk regarding this.
Thanking you all.