Foreign Minister Tzipi Livni urged the United States to stand firm against Iran's nuclear program and extremists in the region during a telephone conversation she held on Monday with Vice President-Elect Joe Biden. It was the first such conversation between the two since last week's elections. Besides Livni, Biden on Monday also called Defense Minister Ehud Barak and Likud Party leader Binyamin Netanyahu. "There is great importance to our continued partnership against the Iranian threat. Time is not on the side of the moderates. Iran, Hamas and other extremists are testing us. They have to understand that the world will not tolerate extremism and terrorism," she said, according to a statement released by the Foreign Ministry. She also thanked Biden for the work he had already done on behalf of Israel and said she looked forward to working with him in the future to advance issues of joint concern to Israel and the United States. A spokesman for Barak said that the defense minister and Biden, who have known each other for 15 years, discussed all the regional issues, including Iran. Barak congratulated Biden on his victory last week in the American elections. Netanyahu's spokesman Yossi Levy said that the conversation with Biden was also very friendly and that the two had known each other for over 20 years. The telephone calls with Biden came in the aftermath of a meeting in Sharm e-Sheikh Sunday, on the sidelines of the Quartet gathering, in which senior US and European officials met with several Arab leaders who are worried about the international community negotiating a deal with Iran that would give the Islamic Republic more power in the Middle East. President-elect Barack Obama had said he was more open to holding talks with Iran on the country's controversial nuclear program. However on Friday, at his first press conference, Obama said that a nuclear Iran was unacceptable.