Bulgaria faced prolonged political instability on Monday after Sunday's national election appeared to result in a razor-thin victory for the centre-right GERB party of former prime minister Boyko Borissov and no clear government prospects emerged. With 95% of ballots counted, GERB had won 23.9% of the vote, only just ahead of the new anti-establishment party There Is Such a People (ITN) of popular TV talk show host and singer Slavi Trifonov, with 23.7%.

Borissov, 62, was unlikely to succeed in forming a functioning coalition, even if final results confirm his party ahead, after he failed to do so following an inconclusive parliamentary election in April. He won that vote with 26.2%.

Most political parties refuse to work with the former bodyguard, with many Bulgarians blaming him for allowing pervasive corruption to fester and accusing him of giving tacit support to powerful oligarchs.

Sharp-tongued but debate-shy Trifonov, 54, announced plans to try to form a minority cabinet, which most political observers said was a risky move that put pressure on his likely partners and was difficult toassess.

Arguing a coalition government could foster backroom deal-making, he laid out his list of priorities and ministers, appealing to all parties, including small anti-graft Democratic Bulgaria and Stand Up! Mafia Out!, which have benefited from mounting anger over corruption, to lend him support.

"It is time that everything happens right in front of your eyes, in parliament. Because this is the moral thing to do," he said in a live-streamed speech from his small TV channel.

The three protest parties are not seen securing a parliamentary majority, meaning ITN would need the backing of traditional parties such as the Socialists or the ethnic Turkish MRF party to replace the current interim cabinet.

A third election can not be ruled out, meaning Bulgaria may face difficulty tapping the European Union's multi-billion euro coronavirus recovery package or approving its 2022 budget plans.

Final official results are expected on Thursday.