The US urged Russia and Ukraine on Tuesday to end their dispute over natural gas supplies that has caused a sharp decline in shipments throughout Europe.
"Russia and Ukraine should get together, come to the table, work out the differences that exist between them in what would appear to be a commercial dispute," State Department spokesman Sean McCormack said.
Russia and Ukraine have been unable to come to terms on a delivery contract, and Russian natural gas monopoly Gazprom cut off supplies to Ukraine, where they are distributed to European countries.
The two sides were set to resume negotiations Thursday. The European Union has complained that they have failed to live up to their obligations.
"This situation is completely unacceptable," an EU statement said.