(Bloomberg) -- A chunk of the vast fleet of tankers that Russia uses to deliver its crude oil is grinding to a halt under the weight of US sanctions, a sign that tougher measures by western regulators might be starting to have tangible effects on Moscow.Most Read from BloombergS&P 500 Rally Hits a Wall in Run-Up to CPI Report: Markets WrapTrump Asks Supreme Court to Keep DC Election Trial on HoldPentagon Chief Austin in Critical Care for Bladder IssueTrump Says There’s ‘No Way’ Taylor Swift Can