The Palestinians are facing "intensive pressure" not to sue Israel for war crimes at the International Criminal Court should they win upgraded U.N. status this week, an official said on Wednesday.

Speaking to reporters in Ramallah, senior PLO official Hanan Ashrawi said the Palestinian leadership had not given in to heavy international pressure to commit that they would not sue Israeli officials at the ICC should they win recognition as a non-member state at the United Nations.

The new party set up by Israel's former opposition leader Tzipi Livni is likely to fare poorly in the January elections and have no impact on the strength of the rightwing bloc, a poll said Wednesday.

Livni returned to politics on Tuesday after a seven-month hiatus, announcing the creation of a new faction called HaTnuah, hoping to affect what surveys have suggested will be an easy electoral win for Prime Minister Benjamin Netanyahu and his bloc of rightwing and religious allies.

France on Wednesday warned the Palestinians against taking Israel to the International Criminal Court should they win upgraded U.N. status this week, saying it would it damage peace efforts.

Foreign Minister Laurent Fabius acknowledged it would be within the Palestinians' rights to join the ICC and pursue Israel should they win recognition as a non-member state at the United Nations.

Israeli troops on Wednesday crossed the barbed wire in al-Wazzani hills and entered into an area that the Lebanese Army has expressed reservations over, the National News Agency reported.

NNA said the 11-member Israeli unit crossed the technical fence and marched 10 to 15 meters into the disputed area at around 8:00 am.

The United States publicly disagreed with France, one of its closest allies, on Tuesday, after Paris said it would back a Palestinian bid for enhanced status at the United Nations.

"We obviously disagree with our oldest ally on this issue. They know that we disagree with them," State Department spokeswoman Victoria Nuland said. "But it's their sovereign decision to make, how to proceed."

The Israeli foreign ministry said on Tuesday that a French decision to back a Palestinian bid for enhanced United Nations status at the General Assembly "comes as no surprise."

French Foreign Minister Laurent Fabius told parliament that Paris would say "yes" in Thursday's vote on a call for "non-member observer state" status for the Palestinians, recalling France's "consistent position" on the issue.

There was "no mistake" in an Israeli air strike that killed 12 Palestinians in Gaza, including 10 from the same family, the Israeli army said on Tuesday, saying the raid targeted a "terror operative."

The November 18 strike, in the middle of a conflict between Israel and Palestinian militant groups in Gaza, hit the home of the Dallu family, killing 10 of its members, and two neighbors, including five children and five women.

Israel's former foreign minister Tzipi Livni announced her return to politics on Tuesday at the helm of a new party called The Movement, nearly seven months after stepping aside following a primary defeat.

"I have decided to return to politics... and to create a political party that I have named 'The Movement'," she told a press conference in Tel Aviv eight weeks before snap elections on January 22.

Prime Minister Benjamin Netanyahu's Likud faction shifted further to the right on Monday, with the more moderate members of the ruling party faring poorly in a primary vote ahead of January elections.

The two-day poll, extended from Sunday after technical failures in the computerized system caused significant delays, ended on Monday night with nearly 60 percent of the Likud's 123,000 members casting their vote.

U.N. chief Ban Ki-moon called Monday for renewed efforts to achieve a two-state solution in the Middle East following last week's ceasefire between Israel and Hamas.

"More than ever, we need a negotiated two-state solution ending the occupation and the conflict," he said at the inauguration of a new center for interreligious dialogue in Vienna.