The U.S. worked Sunday to ramp up diplomatic and financial pressure on Russia over Ukraine, promising to put Moscow on the defensive at the U.N. Security Council as lawmakers on Capitol Hill said they were nearing agreement on “the mother of all sanctions.” The American ambassador to the United Nations …

As Russia continues to mass forces on its border with Ukraine, top Russian and U.S. diplomats are likely to meet this week in an effort to defuse the crisis. Republicans and Democrats appeared increasingly united in their efforts to pressure Russian President Vladimir Putin to pull back his forces, with …

Russia further boosted troop levels on the Ukrainian border this weekend, adding to President Vladimir Putin’s options should he decide on a military incursion, Pentagon spokesman John Kirby said. “He can execute some of those options imminently,” Kirby said on “Fox News Sunday.” “Imminent means it could happen really, honestly, …