Brent crude fell for a second day amid speculation that the biggest weekly rally since February on tension between Ukraine and Russia may be excessive. West Texas Intermediate was steady. Futures dropped as much as 0.5 percent in London . The U.S. and its European allies urged Russia to help calm the Ukraine crisis after four-nation talks produced an accord aimed at easing the worst standoff since the Cold War . WTI’s discount to Brent shrank as the Obama administration said it will postpone a ruling on the Keystone XL pipeline. “Oil futures went up quite a bit over the last week and now we’re seeing some selling,” Victor Shum , a vice president at IHS Energy Insight in Singapore, said by phone today. The Ukraine crisis “has added to geopolitical tension but no oil supply has been disrupted.” Brent for June settlement declined as much as 54 cents […]