The ruble erased gains against the dollar after crude oil fell on speculation a storm in the Gulf of Mexico will have limited impact on oil production.

The ruble strengthened less than 1 percent to 31.8500 per dollar by the close in Moscow. The currency was little changed against the euro at 39.8750 and against the central bank’s currency basket, which is 55 percent dollars and 45 percent the common currency.

Crude gave up its earlier advance, retreating 1.3 percent to $94.86 a barrel in New York, as Tropical Storm Isaac was forecast as a Category 1 storm, the weakest on the five-step Saffir-Simpson scale. Brent crude, a benchmark for Russia’s Urals blend, slid 1.2 percent to $112.27 a barrel.

Investors pared bets the ruble will weaken against the dollar, with non-deliverable forwards showing the currency at 32.3316 in three months versus 32.3655 on Aug. 24.

The extra yield investors demand to own Russia’s dollar bonds over U.S. Treasuries rose two basis points to 225, according to JPMorgan Chase & Co.’s EMBI Global Index. Yields on the government’s ruble bonds due April 2021 were steady at 7.86 percent, data compiled by Bloomberg show.

To contact the reporter on this story: Ilya Khrennikov in Moscow at ikhrennikov@bloomberg.net

To contact the editor responsible for this story: John Viljoen at jviljoen@bloomberg.net