JERUSALEM -- Washington's Middle East envoy faced a new obstacle Thursday as he launched his latest attempt to revive Israeli-Palestinian peace talks: Israel wants to keep troops on the West Bank's border with Jordan even if a deal is reached.

Palestinians rejected Israeli Prime Minister Benjamin Netanyahu's demand, made just before U.S. envoy George Mitchell arrived in Israel on Wednesday.

Mr. Mitchell has been laboring without success for a year to get both sides back to the negotiating table, and Mr. Netanyahu's new demand made his mission even more formidable.

Mr. Netanyahu said Israel must maintain a presence "on the eastern side of a prospective Palestinian state" to keep militants from using the territory to launch rockets at Israel's heartland. The eastern side of such a state would be the part of the Jordan Valley that lies in the West Bank.

Saeb Erekat, a confidant of Palestinian President Mahmoud Abbas, called the demand "absolutely unacceptable."

"The borders of the state of Palestine will be Jordan," he told Israel Radio. "The Jordan Valley is ours, is Palestine. Why do they insist on being on our territory?"

The Palestinians have refused to sit down with Israel until it stops all construction in the West Bank and east Jerusalem, saying it is eating up lands they claim for their future state. Israel, which captured both areas in 1967, has slowed settlement construction in the West Bank, but has applied no restrictions in east Jerusalem, which Mr. Netanyahu hopes to retain.

The hard-line Israeli leader heads a coalition largely opposed to the sweeping territorial concessions that would be necessary to clinch a peace deal with the Palestinians. He had long refused to endorse the concept of Palestinian statehood, doing so only in June under intense U.S. pressure.

Mr. Mitchell is to meet with Mr. Netanyahu and other senior Israeli officials on Thursday, and with Palestinian officials in the West Bank on Friday.

Copyright 2010 Associated Press