Richer EU member states need to show more solidarity with new members like Bulgaria and Romania to boost their economies, argued influential Bulgarian banker Tsvetan Vassilev.

Speaking in an interview for German paper Handelsblatt, Vassilev argued that the EU has shown more solidarity with poorer members like Greece and Portugal in the past, and said the Union must return to those values.

"Durign the last 30 years chiefly German and French companies started to work in Eastern Europe without any competition. Instead of that, we needed help to develop our own economies, but this somehow did not happen," commented the Bulgarian businessman.

At the same time, Vassilev argued that companies coming from Western Europe have often little knowledge of the inner economic and political workings in eastern EU member states.

The Bulgarian banker downplayed western member states' fears of an oncoming migrant wave from Bulgaria and Romania, after the fall of all working restrictions January 1, 2014.

In the interview, Vassilev, who owns the influential Corporate Commercial Bank, estimated that companies controlled by him make for over 10% of Bulgaria's GDP.

"I employ 20,000 people in Bulgaria, and indirectly that number is over 150,000. My businesses make over 10% of Bulgaria's GDP. Given this, I know very well Bulgaria's true problems," said the banker.

In the Handelsblatt interview, the influential banker admitted that corruption is a grave ill in Bulgaria, but said this is something that politicians, rather than businesspeople, are to be held responsible for.

"The most serious problem in Bulgaria is that politicians think they are all powerful and untouchable. This will change sooner or later. The crisis speeds up those processes and the political system in Bulgaria will very soon change," concluded Vassilev.