With no domestic oil refining capacity, Estonia relies entirely on oil product imports from Finland and Lithuania to satisfy domestic demand. The country has a large marine bunker fuel market and has historically been an established transit route for Russian oil product exports. However, this has been on the decline as political tensions between the two countries rise, and Russia bolsters its northwestern port infrastructure. The Estonian government has made much progress in recent years to monitor and address its historic illicit 'grey' fuel market and introduced mandatory biofuel blending in transport fuels in 2018. Following LUKOIL's exit, the Estonian fuels market is now more concentrated than ever, with the top four players collectively accounting for over 90% of the retail market volume sales.