The ruble extended its biggest monthly drop since January, with PAO Rosbank, Credit Suisse Group AG and Renaissance Capital seeing more weakness in the third quarter because of the crisis in Greece and external debt payments. Russia’s currency retreated less than 0.1 percent to 55.764 against the dollar at 4:45 p.m. in Moscow. The ruble is headed for a 6.2 percent drop this month, the most since January, while Brent crude is 4 percent weaker in June. Bonds gained as the Finance Ministry said it plans to sell 275 billion rubles ($4.93 billion) of debt in the third quarter, the most since the first three months of 2014. The rising likelihood Greece will leave the euro region is one more reason to be wary of the Russian currency. Oil-price risks and looming foreign-debt payments, in addition to the central bank’s foreign-currency purchases, will continue exerting pressure on the ruble […]