Rightist leader and former Bulgarian PM Ivan Kostov has expressed confidence that his Democrats for Strong Bulgaria will remain in parliament following summer 2013 elections.

In an interview for bTV Sunday, Kostov saw no worry in the ultimate falling apart of the rightist Blue Coalition that his DSB is part of, due to recent turmoil in the other main coalition partner, the Union of Democratic Forces.

"You will see at the next elections that DSB will enter parliament even without the UDF," said Kostov.

"The Blue Coalition has always been the coalition for those who never voted for current ruling party GERB or the Ahmed Dogan's Movement for Rights and Freedoms. Those people will now vote for DSB," added he.

Kostov was referring to recent suspicions that UDF might coalesce with GERB following an agreement between UDF leader Emil Kabaivanov and GERB chair and Bulgarian PM Boyko Borisov for a UDF-sponsored nomination of a constitutional judge in place of the tainted candidacy of Veneta Markovska.

Leading UDF MPs dissented with the agreement and refused to file a candidacy, upon which they were expelled from the party.

The nominee of the UDF leadership, former Bulgarian President and UDF chair Petar Stoyanov, declined the nomination.

"I think that President Stoyanov did well, because otherwise he would have dealt a heavy blow to the right," commented Kostov.

According to the rightist leader, discontent with the rule of center-right GERB is growing, which will pave the way for a stronger support for authentic rightist parties.