Transdniestria, a narrow sliver of land between the Dniester river and Ukraine, broke away in 1990, fearing that its mainly Slavic population could be marginalized if Moldovans united with ethnic kin in Romania, a prospect that has never materialized.

The separatists fought a brief but bloody war with Moldovan troops in 1992. In 2006, Transdniestria voted in a referendum to become part of Russia. Moscow has 1,200 troops, which guard its Soviet-era facilities, and 450 peacekeepers in the region. But in a move that may signal chilling ties, Russia's central bank warned Russian banks that Transdniestria's Gazprombank through which Moscow transfers its aid, "takes part in improper financial operations ... of profit laundering," the paper cited sources in the Russian president's office as saying.

Russia's central bank recommended that Russian banks freeze their financial operations with Gazprombank, Kommersant wrote.

Gazprombank, the region's largest, is headed by Oleg Smirnov, a son of Transdniestria's veteran leader Igor Smirnov. Kommersant said Russia had repeatedly demanded that this bank and Transdniestria's central bank be independently audited.

Russian and separatist officials could not be immediately reached for comment.

Kommersant said the financial aid, provided by Moscow since 2008, stopped flowing last spring when Russia transferred 414 million rubles ($13.63 million)for the first half of 2010.

The cash is used to supplement the tiny pensions of the local elderly population. Monthly local payments of $15 to each of the region's 137,000 pensioners are popularly known as "Putinka" after Russia's powerful Prime Minister Vladimir Putin.

Russia still financially supports Georgia's breakaway South Ossetia and Abkhazia regions which it recognized as independent states after fighting a five-year war with the Caucasus nation in August 2008.