Prime Minister Sergei Stanishev officially invited Sofia mayor Boiko Borissov to a public debate on the future development of Bulgaria, Bulgarian news agency Focus said.

In an open letter Stanishev invited Borissov, who is also leader of the biggest  party in opposition the Citizens for the European Development of Bulgaria (abbreviated as GERB in Bulgarian), to the debate. Stanishev is leader of the senior partner in the ruling coalition the Bulgarian Socialist Party.

"With this letter I confirm my invitation to you for a public debate on the perspectives Bulgaria has. I am convinced that Bulgarian citizens have the right to witness an open and public debate between the leaders of the two most influential parties in the country and see the differences between us in how we see the country's future. I am ready to negotiate the place, time and agenda of the debate," Stanishev's letter said.

Borissov;'s first reaction to the letter was that he would accept the invitation but he was worried about Stanishev's behaviour at the debate.

On October 9 2008, GERB, together with other right-wing parties, presented Stanishev with a petition asking for his resignation. It was signed by 1 053 000 people. Stanishev accpeted the petition but according to some media called the politicians "clowns".

"Stanishev has to apologise for his words and arrogant behaviour by calling GERB and the other right-wing parties clowns," Borissov was quoted as saying by Focus. "I don't know what I will do if he starts the debate with the same words and calls me clown. I can not say how I would react to these words," Borissov, who is a former bodyguard and former interior ministry chief secretary, said.

Borissov again said that some of the Bulgarian companies that funded Stanishev's election campaign in 2005 were investigated by the European Commission for abuse of EU funds, something which Stanishev has denied.

The next general elections are scheduled for the spring or summer of 2009.