* Bratusek hoping for centre-left coalition

* Snap parliamentary election expected on July 13

* Centre-right opposition marked big win in EU elections last week

By Marja Novak

LJUBLJANA, May 31 (Reuters) - Slovenia's Interim Prime Minister Alenka Bratusek, who helped save the country from an international bailout last year, announced the formation of a new centre-left party on Saturday before a snap parliamentary elections in July.

Slovenia was plunged into a political crisis earlier this month when Bratusek resigned as prime minister, having lost a leadership battle for the centre-left Positive Slovenia party. She is still leading a caretaker government.

A euro zone member, Slovenia narrowly avoided having to be bailed out in December by pumping some 3.3 billion euros of budget funds into its mostly state-owned banks that were beset by bad loans.

Her new party, the Alliance of Alenka Bratusek (ZAB), hopes to form an informal coalition with other centre-left parties before the election expected on July 13 so as to attract more voters.

Last week, the centre-right opposition Slovenian Democratic Party scored a landslide victory in the European Parliament elections, winning 24.9 percent of the vote and 3 out of 8 Slovenian seats in the EU parliament.

"We are gathered here to find new energy for the necessary changes in the country ... therefore I invite our allies to join us," Bratusek told the founding congress of her party.

She said the party's aim was to create more jobs and give a boost to the economy while perserving the environment and human rights.

She also said the party will support privatisation but warned against massive sell-offs.

"We will not privatise blindly but I will not give up searching the necessary development capital for our companies," Bratusek said.

Last year her government earmarked 15 firms for privatisation of which two have been sold. Others, including telecoms operator Telekom Slovenia and the country's second-largest bank Nova KBM are due to be sold by 2015.

OPINION POLL

Opinion polls compiled since the break-up of Bratusek's previous party on April 26 started incorporating a hypothetical new party founded by her into their research, finding that it would gain between 1.6 and 12.2 percent of the vote.

Analysts said Bratusek's new party stood a good chance of crossing the 4 percent threshold needed for parliament but that centre-left parties would have to cooperate rather than compete in the election if they wanted to form the next government.

"If the centre-left parties would manage to form a united front they would have big chances at the election. But if they remain fragmented, the centre-right parties would be in a better position to win the election," said Tanja Staric, an analyst at daily Delo.

On Monday, popular law professor Miro Cerar will form another new centre-left party. Bratusek has already said she is willing to cooperate with his and other parties to prevent a victory of the centre-right opposition after their European Parliament win last week.

"Despite increasing fragmentation, the most likely scenario for the early election outcome is still a leftist parliamentary majority," said Otilia Dhand, Vice President of consultancy Teneo Intelligence.

"Anti-austerity leanings in the electorate and the likely higher turnout will favor the left," she added.

Turnout in the European elections was only 24.1 percent and is expected to be much higher in the parliamentary poll in July at about 60 percent.

Bratusek's ex-party Positive Slovenia received only 6.6 percent of the vote in the European election last week and did not make it to the EU parliament. (Reporting By Marja Novak; Editing by Raissa Kasolowsky)