Russia's leading gas exporter has said Belarus must pay three times more for its gas supplies in the future.
The Belarussian economy is dependent on Russian gas
Gazprom, which is negotiating future supply arrangements with the former Soviet republic, wants it to pay near European rates for its gas imports.
Belarus, a close ally of Moscow, was the only ex-Soviet republic not have Russian gas prices hiked last year.
Belarus said it was hopeful of reaching a compromise acceptable to both sides, on the basis of a decade-old alliance.
Growing tension over what Belarus pays for its neighbour's gas comes three months after a similar dispute between Russia and Ukraine.
Gazprom temporarily turned off gas supplies to Ukraine in January after Kiev refused to pay the higher charges demanded by the company.
Belarus currently pays $46 per 1,000 cubic metres for its Russian gas, the lowest of any former Soviet republic.
Gazprom vice chairman Alex Ryazanov said Belarus must pay substantially more for its gas in the future.
"For us, raising prices for CIS countries is not a political decision, but (the) real economy in which we live today," he told the NTV television channel.
Belarus has strong political, economic and military ties with Moscow.
However, these could be tested by a prolonged dispute over gas since experts believe that Belarus' struggling, state-controlled economy could flounder without cheap Russian gas.
The Belarussian energy minister said he believed a deal would be reached under the terms of the 1996 "union agreement", which cemented an alliance between the two states.
"The price for Belarus cannot be set at either European or any other level," Alyaksandr Aheyew told Belarussian state television.
"This price should be mutually beneficial."
Gazprom will present its formal demands to Belarus later this month.