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By Tsvetelia Tsolova
SOFIA, March 7 (Reuters) - The leader of a new pro-business Bulgarian political party said she will not support any coalition after elections in May, making an extended period without government more likely for the EU's poorest country.
The big political parties have rigged previous elections and cannot be trusted, Meglena Kuneva, a former European Union commissioner who founded the Bulgaria for the Citizens party, told Reuters in an interview on Thursday.
Support for her party, at 5-6 percent in an opinion poll published before Prime Minister Boiko Borisov's rightist GERB government resigned on Feb. 20 amid violent protests over electricity bills and corruption, may rise due to voter disgust with traditional groups, she said.
With GERB and the Socialists neck-and-neck on 22-23 percent in the poll and the ethnic Turkish MRF on 6-7 percent, analysts say it is almost certain no party will have enough votes to form a government on its own.
"What we have decided for now is that Bulgaria for the Citizens does not see a chance for coalitions," said Kuneva, whose success as a minister in negotiating EU accession in 2007 may win her respect from voters eager for competent management.
"The parties did not do anything to show they will not try to manipulate the vote - so the base of trust is poisoned. There is no need to buy poisoned fruit," she said.
The wave of protests, in which three people set themselves on fire and hundreds of thousands rallied in the country of 7.3 million, makes the election result unpredictable.
Demonstrations began when Bulgarians, already impatient with corruption and a sluggish economy, were angered by rising utility bills in a country where the average monthly wage is 400 euros ($520) and pensions less than half that.
Low-level corruption, low incomes and poor infrastructure make life a struggle in Bulgaria, whose population has shrunk 7 percent in a decade due largely to emigration. Gross domestic product per capita is less than half the European Union average in purchasing power parity terms and economic growth fell to 0.8 percent in 2012.
Kuneva, 55, said she will work to ensure rule of law, transparent public procurement deals and access to financing for small companies to build investor confidence, so that some 150,000 new jobs can be created in two years.
"What we need to do is to restore trust ... When I promise something, I see it through to the end. This is what we miss - that when you promise something you are actually going to do it," she said.
She won 14 percent of the vote as an independent in a 2011 presidential election on an anti-graft and pro-business agenda and has since formed her own party.
GERB has said it will not work with another party and Kuneva's reluctance on coalition deals means the most likely solution would be an alliance of the Socialists and MRF. But they may struggle to win enough votes between them for a working majority without a third partner.
The discontent with the main parties could give a boost to nationalist parties such as Attack, which blames Roma gypsies and ethnic Turks for many of the country's woes.
If the protests radicalise public opinion, Kuneva's moderate tone and personality may count against her, analysts say.
"Kuneva is a gentle and calm person in these hard times. When public opinion is polarising her voice may remain unheard," said Andrey Raichev, an analyst with Gallup International.
"Her success will depend on her, how she can avoid that problem and send her message to the people."
($1 = 0.7692 euros) (Editing by Jason Webb)