Washington (CNN) -- President Barack Obama on Thursday made official the long-held but rarely stated U.S. support for a future Palestinian state based on borders that existed before the 1967 Middle East war. In the past, the United States has unofficially backed a two-state solution to the Israel-Palestinian conflict based on the borders in place prior to the war 44 years ago in which Israel seized the West Bank, Gaza Strip, Golan Heights and Sinai Peninsula. In a major speech Thursday, Obama became the first president to formally endorse the policy, but he also acknowledged the need for modifications through the negotiating process due to conditions on the ground.
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NEW: Romney says Obama threw Israel "under the bus"
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President Obama formalizes a longstanding but rarely expressed U.S. position
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A Palestinian state must be viable, while Israel must be secure, Obama says
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Netanyahu rejects Israel's withdrawal from existing population centers
"He has disrespected Israel and undermined its ability to negotiate peace," @placeholder said in a statement.