The U.S. and the European Union imposed the most aggressive sanctions to date on Russian business and said more may follow, acting after weeks of threats to squeeze the $2 trillion economy over the confrontation in Ukraine. The benchmark Micex index dropped 1.9 percent as of 10:54 a.m. today in Moscow to the lowest since May 30 and the ruble slid 0.7 percent against the central bank’s basket of currencies after the Obama administration unveiled the sanctions. Targeted companies include OAO Rosneft (ROSN) , Russia’s largest oil company, natural gas producer OAO Novatek (NVTK) , OAO Gazprombank, the country’s third-largest lender, and eight defense firms. EU leaders agreed to blacklist companies and halt lending to public-sector projects in Russia. “These sanctions are significant,” U.S. President Barack Obama said yesterday at the White House. “But they are also targeted, designed to have maximum impact on Russia while limiting any spillover […]