Geneva cantonal minister Carole-Anne Kast says Bern gave in too easily to France over who pays for last month's G7 summit in Évian.
The canton is left with CHF 31.6 million in costs, of which the Confederation will cover CHF 12.5 million.
Geneva is still asking Paris to pick up the remaining CHF 20 million, but the French side has so far declined — a stand-off Kast warns could weigh on cross-border relations.
The Fédération des Entreprises Romandes puts business losses across the region at around CHF 300 million, which Kast called "very substantial".
The canton has ruled out compensating cafés and restaurants for lost trade during the summit.
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