Addressing the press after a session of the party's executive council, NSi head Matej Tonin said that the potential centre-left partners had in fact made a big effort to appease the NSi in the talks and that it would be unfair to say the decision was a result of the final version of the coalition agreement.
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Tonin listed all the things the NSi managed to negotiate, including a scrapping of the top income tax bracket and equal funding for private education, indicating that the NSi's wish to "also give people a choice in public healthcare", was the only thing the partners were not willing to compromise on.
Still, the NSi's success in the talks notwithstanding, Tonin fears "there is a very large chance that we would not have been able to implement it in reality".
He spoke of the possibility of the Left, the far-left party which was not invited to talks by LMŠ leader Marjan Šarec, voting with a centre-left coalition and overriding the NSi, while he also highlighted continuing tensions in the coalition talks among the partners in the outgoing government. "Some of their issues are of a very personal nature," he added.
Expressing serious concerns about the stability of such a diverse six-party coalition, Tonin said Slovenia needed a strong and stable ruling coalition and suggested the NSi's decision might contribute to the centrist parties rethinking their position on not talking to election winner Janez Janša of the Democrats (SDS).
While one possible scenario is that the centre-left parties now invite the Left to negotiations, Tonin believes it would be best if the SDS is joined by the LMŠ the NSi and another party that he did not name for a comfortable four-party majority - the only party that would enable this is the Modern Centre Party (SMC) of outgoing PM Miro Cerar.
Tonin explained today's decision only applied to the first round of the appointment process for PM-designate, which expires on 23 July.
He added that the false impression was being created that the parties are pressed for time, saying that, according to his knowledge, the final deadline is roughly 15 August. An early election is also a possibility, but Tonin expects it would bring a very similar situation.
The NSi will meet the right-wing SDS on Tuesday and expects to get a coalition agreement proposal from Janša.
The LMŠ did not yet wish to comment on the new situation, saying it will take time to reflect on it.