US envoy George Mitchell kicked off a fresh round of Middle East shuttle diplomacy on Thursday with a somewhat tense meeting with Israeli Foreign Minister Avigdor Lieberman.

In response to Lieberman's earlier declarations that Israel is not bound by previous land-for-peace understandings that the Palestinians have consistently violated, Mitchell insisted that the final outcome of the Middle East peace process must be a sovereign Palestinian Arab state.

The Foreign Ministry released a statement reporting that Lieberman reminded Mitchell that the land-for-peace process has been going on for 15 years, under numerous Israeli governments prepared to surrender most of the demanded territories.

Lieberman concluded: "Thus far, the traditional approach has not brought any results or solutions."

Mitchell also met with Israeli President Shimon Peres who, while less direct than Lieberman, told the American that Israeli is ready for peace, but not at the expense of its own security.

In remarks to the press, other Israeli ministers took Lieberman's arguments one step further.

Interior Minister Eli Yishai told Army Radio that with the Palestinians having proven that they would use an independent state to threaten Israel, that option must be taken off the table. Instead, Israel should follow Prime Minister Benjamin Netanyahu's previously stated plan to focus on boosting the Palestinian economy, while indefinitely putting land concessions on hold.