Bulgarian PM Boyko Borisov's meeting with US President Barack Obama has brought no advance in bilateral relations, argued opposition Bulgarian Socialist Party leader Sergey Stanishev.

"The White House's reaction to Borisov's visit has been very much equal to a nothing that still comes from the heart," joked Stanishev at a press event Tuesday.

The Bulgarian Socialist leader, who also chairs the Party of European Socialists, was referring to Obama's assurance that Bulgaria is playing the role of a responsible partner to the US.

"Apart from the US not criticizing Bulgaria for corruption and organized crime, the visit has achieved no palpable results," added Stanishev.

"For instance, we still don't know when the US visa regime for Bulgaria will be abolished," said he.

Stanishev also added that the Bulgarian public needs to know why exactly vice-PM and Minister of Interior Tsvetan Tsvetanov has stayed for a second week in the US.