Russian energy giant Gazprom said on Tuesday it may switch off gas supplies to Moldova if Moldova fails to comply with its payment obligations by 20 October.
It also said it reserved the right to annul its gas supply contract with Moldova at any stage over Moldova's historical debts, in a long-running dispute.
Gazprom has threatened similar moves before amid political tensions between Moscow and an avowedly pro-Western government in Chisinau.
Moldova, one of Europe's poorest countries, is reliant on Russian gas, the price of which has surged this year because the contract with Gazprom fluctuates from month to month based on the spot market price of gas and oil.
Gazprom also said the Ukrainian energy firm Naftogaz had refused to provide it with sufficient transit capacity, and that it was therefore cutting gas exports to Moldova by around a third to 5.7 million cubic metres per day this month.
High inflation, notably for energy, sparked street protests in Moldova last month demanding the resignation of the pro-Western president, Maia Sandu, who was elected in 2020 and is pushing for Moldova to be admitted to the European Union.