SOFIA - Bulgarians head to the polls on Sunday for their sixth parliamentary election in three years, but analysts say the vote is unlikely to yield a stable government.

Bulgaria has been plagued by revolving-door governments since anti-corruption protests in 2020, with a series of elections producing shaky coalitions that swiftly crumbled.

The latest opinion polls suggest no party will win a majority, setting the stage for a new round of coalition talks once the votes are in.

Sunday's vote was triggered by the collapse in March of a coalition comprising the center-right GERB party and the We Continue the Change (PP) party

Polls opened at 7 am (0400 GMT) and will close at 8 pm (1700 GMT), with exit polls due to be announced immediately after polling stations close. The first partial results are expected around midnight (2100 GMT).

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Bulgaria needs a period of stable, well-functioning government to accelerate the flow of EU funds into its creaking infrastructure and nudge it towards adopting the euro and fully participating in Europe's open-border Schengen Area.

Plans to join the eurozone have already been pushed back twice because of missed inflation targets. Accession is currently slated for Jan 25, 2025.

Failure to form a stable government would raise the risk of further delays, Teneo analysts said in a report last week.

Bulgaria has so far only received 1.4 billion euros out of 5.7 billion euros in available grants from the EU's Recovery and Resilience Facility (RRF), they said.

READ MORE: EU: Bulgaria could adopt the euro from 2025 if ready

Sunday's vote was triggered by the collapse in March of a coalition comprising the center-right GERB party and the We Continue the Change (PP) party.

The latest Gallup poll, published on Friday by the BTA news agency, put GERB ahead with 25.9 percent of the vote, followed by three parties in a tight race for second place.