The ruble weakened, following the biggest drop in more than four months, after Citigroup Inc. said the currency will remain under pressure until oil ends its declines.

Russia’s currency fell 0.8 percent to 67.4010 against the dollar by 3:16 p.m. in Moscow after strengthening as much as 0.9 percent. The ruble tumbled 3.9 percent on Tuesday as Brent crude slid the most since May 2011. The currency led the declines among emerging markets on Wednesday.

“The currency, and more broadly Russian assets, will find a bottom only when the market somehow reaches the conclusion that the oil prices have no further room to fall,” Ivan Tchakarov, a Moscow-based economist at Citigroup, said by e-mail. “I doubt the market has come even close to thinking that.”

The ruble price of Brent dropped to 3,305, below the average of the past 12 months, as oil extended its two-day loss to almost 10 percent. Russia, the world’s largest energy exporter, gets half of its budget revenue from the sale of oil, products and natural gas.

The ruble weakness and the global market meltdown will prompt the Bank of Russia to keep its key interest rate on hold at the Sept. 11 meeting, Citigroup said. At the same time, the central bank is “unlikely” to tighten monetary policy, Citigroup said. The median forecast of 25 economists surveyed by Bloomberg sees the rate dropping to 10 percent by the end of the year and to less than 8 percent by the end of 2016.

Russian markets may be most affected by any further yuan devaluation because of the nation’s “high” reliance on commodity exports, Bank of America Corp. analyst David Hauner said in an e-mailed note. More than $7 trillion has been wiped from global equities since China’s unexpected devaluation on Aug. 11 as concern deepened the world’s second-biggest economy is slowing more than expected.

The Micex index of stocks fluctuated between gains and losses, while the yield on five-year government notes climbed six basis points to 11.89 percent. The Finance Ministry sold 1.93 billion rubles of 8.32 billion rubles offered of floating-rate OFZ bonds due December 2017 on Wednesday, after canceling the auction last week.

“Oil’s and ruble’s volatility imply limited investor appetite for ruble assets, while the Finance Ministry decided not to offer a premium in order to sell a maximum volume,” Alexey Demkin, head of research at Gazprombank JSC in Moscow, said by e-mail.