The drop didn't seem to worry equity investors, with Rosneft's Moscow-listed stock jumping around 2.8 percent to 30-day highs by 4:30 a.m. ET.
However, the plunge is likely to disappoint Moscow, which is banking on state-owned companies like Rosneft to bolster revenues. The Russian government holds a 69.5 percent stake in Rosneft through state-owned firm Rosneftgaz.
In April, Russian Prime Minister Dmitry Medvedev announced he had signed a resolution requiring state-owned companies to distribute no less than 50 percent of their net profit in dividends. He said the budget was likely to receive an additional 100 billion roubles ($1.6 billion) as a result.
But, Chris Weafer, a senior partner at Macro-Advisory, told CNBC in a phone interview that the urgency to impose those income-generating proposals has somewhat subsided thanks to a slight oil price recovery, continued ruble weakness, and prospects of a Rosneft stake buy-out.
The Russian government is planning to sell stakes in some state-owned firms in another bid to shore up cash. Moscow is expected to maintain a majority stake of at least 50.1 percent in Rosneft, leaving about 19 percent up for grabs.
Economy Minister Alexei Ulyukayev told reporters on Wednesday that they may consider selling stakes to both strategic investors and the stock market, according to Reuters.