The ruble weakened for the first time in five days amid speculation that gains in oil, the main driver for the currency’s movements, will be limited. While Brent crude headed for its biggest weekly increase since March 2009, technical studies suggest that its rally will face resistance at $54-$55 per barrel, Denis Davydov, an analyst at Nordea Bank AB in Moscow, said. As oil trades less than a dollar below that level, traders might be unwinding their positions in the ruble, he said in emailed comments. The currency of the world’s largest energy exporter rallied this week as speculation that oil demand is rising and supplies are retreating buoyed crude prices. Oil, which has traded below its 200-day moving average since July 2014, rose closer to that landmark as Federal Reserve minutes indicated policy makers won’t rush to lift interest rates, making commodities priced in the dollar more attractive. […]