This thesis investigates the geopolitical and economic consequences of "ghost fleets," covert networks of ships that enable the illegal transportation of Russian oil, bypassing international sanctions established after Russia's invasion of Ukraine in 2022. These fleets persistently export substantial amounts of oil despite worldwide limitations by employing strategies like as deactivating Automatic Identification Systems (AIS), faking shipping paperwork, and conducting ship-to-ship swaps in international waters. The study investigates the significant impact of these efforts on the worldwide oil market, namely the disruption of prices and market instability resulting from the influx of discounted Russian oil. This illustrates how phantom fleets undermine the efficacy of sanctions designed to cripple Russia's economy, enabling the nation to sustain income sources that finance its military operations. Empirical evidence and economic analysis demonstrate that nations such as China, India, and Syria persist in importing Russian oil through covert operations, hence exacerbating the challenges associated with enforcing sanctions. The thesis provides a thorough analysis of the European Union's reaction to Russia's aggressive actions, with a specific focus on the difficulties encountered in upholding the effectiveness of sanctions due to the presence of these covert naval fleets. It exposes the shortcomings of existing global regulatory systems, which have difficulties in efficiently overseeing and curbing illicit maritime activity. The research highlights the importance of strengthening international collaboration, enhancing monitoring technologies, and implementing tougher enforcement methods to effectively address the vulnerabilities used by these illegal networks. To summarize, the thesis suggests a thorough revamp of the worldwide sanctions enforcement system, promoting more stringent regulatory supervision, sophisticated technological surveillance, and a better-coordinated international strategy to guarantee the enduring efficacy of sanctions and the stability of global markets. This work emphasizes the persistent danger presented by ghost fleets to the worldwide economic system and emphasizes the need for stronger global governance in a world that is becoming more linked.