RAMALLAH // The deal brokered by US secretary of state John Kerry to restart the Middle East peace process looked increasingly fragile yesterday.
The chief Palestinian negotiator Saeb Erekat is supposed to meet Tzipi Livni of Israel in Washington this week, but an official in the Palestinian Liberation Organisation said Mr Erekat would not go without a formal invitation.
A spokesman for Mahmoud Abbas, president of the Palestinian Authority, has already said they are "awaiting an invitation by Washington". Jay Carney, the White House spokesman, said on Monday that dates were still being finalised for talks and warned of the "enormous challenge" ahead.
Palestinian officials did not say why a formal invitation was required, but the demand suggests that Mr Kerry faces an uphill battle in laying the groundwork for talks that would cover Jewish settlements, borders, possession of Jerusalem and Palestinian refugees.
Mr Kerry has made six trips to the region this year to coax the parties back to the negotiating table after a three-year hiatus.
The European Union is also playing an increasing role. Mr Kerry's breakthrough last week came after the EU announced a ban on financial cooperation and assistance to Israeli institutions in the occupied territories, a move criticised by Israel.
This week the EU made a concession to Israel by blacklisting Hizbollah's military wing, a group that calls for Israel's destruction.
The EU is now considering increasing the pressure on Israel. Its foreign policy chief Catherine Ashton will draft guidelines by the end of the year requiring all products from illegal Israeli settlements in the West Bank, East Jerusalem and the Golan Heights to be labelled as such.
Baroness Ashton says a majority of the EU's 28 member states support labelling settlement products, and that the policy is in line with the EU's view that the settlements are illegal under international law.
The guidelines would be non-binding, but most EU states are expected to adopt them. The United Kingdom and Denmark already label settlement products.
The Palestinians want the West Bank, East Jerusalem and the Gaza Strip as part of their future state.
The Arab League has also endorsed moves towards new peace talks, reiterating last week an offer to recognise Israel in exchange for land swaps and the creation of a Palestinian state.
The US secretary of state reportedly persuaded Mr Abbas to engage in talks with Israel by offering a written guarantee that direct negotiations would be based on the boundaries that prevailed before the 1967 Arab-Israeli war, when Israel captured territories wanted for a Palestinian state.
Though a key Palestinian demand for returning talks, negotiating along the 1967 lines has been rejected by right-wing officials in the government of Benjamin Netanyahu, Israel's prime minister.
Both sides have suggested that they would put any eventual agreement from peace talks to a referendum, a move that analysts say could be aimed at sidestepping elements on either side that could be opposed to the agreement.
"Any agreement with the Israelis will be brought to a referendum," Mr Abbas said on Monday.
Mr Netanyahu also announced on Monday that he was fast-tracking legislation to put any peace deal with the Palestinians to a national referendum. Although polls have shown the majority of Israelis favour a peace deal, hard-line members of the prime minister's coalition do not.
The last round of negotiations collapsed in 2010 because Mr Netanyahu refused to extend a moratorium on settlement expansion.
* Additional reporting by Reuters and the Associated Press