Russia is threatening to suspend supplies of electricity to Belarus if that country does not pay its bills.
Belarus is battling a severe currency crisis, and has seen the value of its money fall by 36 percent.
The Russian state-controlled power group InterRAO said it would stop the flow of electricity on Monday, June 27, if Minsk fails to pay the $54 million it owes.
InterRAO provides at least 10 percent of Belarus's electricity needs.
Russian Finance Minister Alexei Kudrin announced the approval Tuesday of the first $800-million segment of a Russian-led $3 billion bailout loan to help stabilize its western neighbor.