Demand for OFZ bonds is seen as a gauge of investors' sentiment towards Russian assets, given the uncertainty around risks of possible US sanctions against Russian debt that for months plagued markets.
Weekly auctions of such bonds usually shore up the rouble as some investors convert their funds into the Russian currency to buy the papers.
At the first auction, the finance ministry sold 94.7 billion roubles ($1.46 billion) worth of rouble bonds maturing in July 2024, a record volume for one auction, facing demand of nearly 184 billion roubles.
The central bank said in its April report on financial markets released on Wednesday that demand for OFZ bonds was boosted by a globally increased appetite for emerging market assets as well as higher prices of oil, Russia's key exports.
Foreign investors bought 41.6pc of OFZ bonds auctioned by the finance ministry in April, taking their share among holders of these bonds to 27.1pc, the central bank said.
Demand for OFZ bonds on Wednesday was also bolstered by the redemption of OFZ bonds series 26216 worth 250 billion roubles, with part of the money being reinvested into Russian government bonds, analysts said.
At the second auction, the finance ministry sold 38.3 billion roubles worth of bonds maturing in 2034 with demand reaching 51.5 billion roubles.
ROUBLE AT APRIL LEVELS
The rouble firmed to 64.72 against the dollar, its strongest level since April 30, and was up 0.4pc on the day at 64.74 as of 1315 GMT.
Apart from demand related to OFZ auctions, the rouble was buoyed by tax payments as well as hopes for a decline in geopolitical tensions after a Russia-US meeting.
US Secretary of State Mike Pompeo and President Vladimir Putin met on Tuesday, indicating that both sides wanted to improve relations despite lingering discords in issues such as Syria, Venezuela and Ukraine.
The rouble got a boost from the fact that Pompeo met Putin as well as his Russian counterpart Sergei Lavrov, "even though there were no breakthrough agreements," said Rosbank, a subsidiary of Societe Generale.
Versus the euro, the rouble added 0.5pc to 72.41 , also its strongest level since April 30.
By the end of the month, the rouble is expected to get support from monthly taxes that usually prompt export-focused companies to sell foreign currency to meet liabilities at home.
Russian stock indexes were mixed.
The dollar-denominated RTS index was steady at 1,241.3 points.
The rouble-based MOEX Russian index was 0.4pc lower at 2,552.0 points, pressured by a decline in oil prices.