The Obama administration, still struggling to win China's pivotal backing for a new round of United Nations sanctions against Iran, is increasingly worried about gaining the support of some other members of the U.N. Security Council, particularly Brazil, Turkey and Lebanon, according to U.S. and European officials. Officials involved in the diplomacy fear that China's stated opposition to tough new sanctions, if reinforced by other players, could weaken any U.N. penalties against Tehran. Though Brazil, Turkey and Lebanon hold temporary seats and can't veto sanctions—unlike permanent council members including China—they could make it harder for the U.S. to get agreement by sustaining the opposition campaign. Senior U.S. diplomats have intensified discussions in recent weeks with leaders in China, Turkey, Brazil and Lebanon in a bid to push a sanctions vote at the U.N. on Iran by next month. But on Wednesday, Brazilian officials publicly rebuffed the U.S. during Secretary of State Hillary Clinton's visit to the capital, Brasilia. "It is not prudent to push Iran against a wall," President Luiz Inácio Lula da Silva told reporters ahead of their meeting. Afterward, foreign minister Celso Amorim said sanctions "could be counterproductive." Turkish and Lebanese officials have made similar comments in recent weeks. – Wall Street Journal