According to Vassilev, it is economically unprofitable for Central and Western Europe for Bulgaria and Romania to be outside the zone without border control. 

"Every day, 4,000 trucks cross the Bulgarian-Turkish border to Western Europe, but stay for days at the border with Romania. This makes the transported goods more expensive," Vassilev explains. 

The minister also told Die Welt that the additional fee of 20% imposed on the Russian gas transit through Bulgaria will reduce the profit of Gazprom and make the supply more expensive, which in turn makes the import of Russian gas unprofitable for countries such as Austria and Hungary .