Building in the E-1 area between eastern Jerusalem and the West Bank settlement of Maale Adumim would be "especially damaging" to efforts to reach a two-state solution, the State Department said.
"The United States opposes all unilateral actions, including West Bank settlement activity and housing construction in East Jerusalem, as they complicate efforts to resume direct, bilateral negotiations, and risk prejudging the outcome of those negotiations," Mark Toner, the State Department deputy spokesman, said in a statement. "This includes building in the E-1 area, as this area is particularly sensitive and construction there would be especially damaging to efforts to achieve a two-state solution."
The statement Monday came after Israel leaked plans to build in the area, in apparent retaliation for the Palestinians' success last week in winning non-member state status at the United Nations General Assembly.
The first State Department reaction on Friday, by Toner's boss, Victoria Nuland, expressed concern over E-1 while also noting U.S. opposition to enhanced U.N. status for Palestine.
"We’re going to be evenhanded in our concern about any actions that are provocative, any actions that make it harder to get these two parties back to the table," Nuland said.
Toner's statement on Monday was focused only on the proposed E-1 building, suggesting that the Obama administration would be aggressive in opposing E-1 development.
"We have made clear to the Israeli government that such action is contrary to U.S. policy," Toner said. "The United States and the international community expect all parties to play a constructive role in efforts to achieve peace. We urge the parties to cease unilateral actions and take concrete steps to return to direct negotiations so all the issues can be discussed and the goal of two states living side by side in peace and security can be realized."
Israeli governments have long planned such building, which would link the bedroom community of Maale Adumim to Jerusalem, but successive U.S. administrations have opposed it, saying that developing the corridor would cut off Palestinian populations centers from each other in a future Palestinian state.
E-1 was a flashpoint of tensions between the administration of President George W. Bush and Israeli Prime Minister Ariel Sharon.