The chief executive of Russian gas exporter Gazprom accused Kiev of adopting an "unconstructive" position in gas talks and of using blackmail to try to get an "ultra-low" price.
Speaking to Russia's Prime Minister Dmitry Medvedev in a meeting open to reporters, Gazprom's CEO Alexei Miller said the debt Gazprom was asking for was "less than that which was required for the time period."
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Ministers are also looking at schemes such as “lock-in agreements” to reduce the 250,000 sales that fall through annually.
Staff have racked up hundreds of thousands of dollars in fees as Robert Mueller and House and Senate committees probe Moscow’s meddling.
It is "clear" ministers cannot proceed with the current Bill, Sir Keir said, threatening to "work with all sides" to ensure revisions.