The future relationship between Ukraine and natural gas company Gazprom depends on resolving lingering debt issues, the Russian company said.

Gazprom says it's owed $5.3 billion from Ukrainian energy company Naftogaz. Similar debt issues in 2006 and 2009 resulted in suspension of gas deliveries, and Gazprom said it's time to pay up.

"The future relationships between the companies are fully dependent on settling the debt payout issue," the company's board said in a statement Tuesday.

Political upheaval in November saddled an already struggling Ukrainian economy with significant debt. In August, the International Monetary Fund distributed $1.4 billion in assistance to Kiev, but said Naftogaz debt was one of the factors contributing to deeper recession in Ukraine.

Members of the Ukrainian parliament met Wednesday in Moscow with their Russian counterparts to discuss ongoing tensions between both sides. A former Soviet republic, Ukraine this week ratified an association agreement with the European Union.

Most of the Russian gas bound for Europe runs through Ukraine.