A month after Iran played war games in the strategic Strait of Hormuz, warning U.S. aircraft carrier USS John C. Stennis not to return to the area, another U.S. carrier sailed into the Persian Gulf and close to the Iranian coast on Tuesday. Although the USS Abraham Lincoln was escorted by a cruiser and a destroyer, an Iranian patrol ship came as close to it as three kilometres, according to one BBC reporter who was aboard the U.S. vessel. The carefully choreographed U.S. move came on the same day the U.S. Treasury released a much-anticipated guidance on the scope of new sanctions against Iran’s financial institutions introduced by the Obama administration on Dec. 31. The West accuses Iran of pursuing a clandestine nuclear weapons program, a claim Tehran denies, insisting its uranium enrichment activities are peaceful. One fifth of the world’s oil supply moves through the Strait of Hormuz, a crucial bottleneck Tehran recently threatened to close in retaliation for U.S. sanctions targeting the sale of Iranian oil.