/ʌnˈɔːθəraɪzd ˌæˌnɛkˈseɪʃən/ – Phrase
Definition: sáp nhập trái phép.
A more thorough explanation: Unauthorized annexation refers to the act of taking over or incorporating a territory or property without proper legal authority or permission. This term is often used in the context of international law to describe the illegal acquisition of land or property by a state or entity without the consent of the rightful owner or governing authority.
Example: The unauthorized annexation of the neighboring property led to a legal dispute between the two parties.