"Any larger sum is under a big question mark," the source said.
Russia reduced the former Soviet Union's debt to the Paris Club after it completed a plan in August to repay part of the debt early.
Overall, from mid-July, $15 billion was paid to the creditor nations. On July 15 and 29, $13 billion was transferred in two tranches to 11 creditor nations: Australia, Britain, Canada, Denmark, Finland, France, Germany, Holland, Italy, Sweden, and the United States.
The remaining $2.3 billion was transferred on August 19 and 22 to another five creditors: Austria, Belgium, Japan, Norway and Spain.
Finance Minister Alexei Kudrin had previously said that Russia could propose another redemption to the creditor nations under agreements reached in May.
Early debt repayment is a boon for the Russian economy, because the country economizes on interest payments and so can allocate more funds for social-economic projects.
