Ismail Haniya, the Palestinian prime minister, on Friday asked Mahmoud Abbas to back down for the sake of Palestinian unity after Israel's killing overnight of Jamal Abu Samhadana, a leader of the Popular Resistance Committees (PRC) group who was also appointed by Hamas to serve as a senior security chief.

The Palestinian president will hold a referendum on July 31 on the statehood proposal, officials say. Abbas signed a decree on Friday to hold the controversial referendum, sources in his office said.

The plan favours a two-state solution to end the conflict with Israel.

A referendum would be seen as a confidence vote on the government run by the Islamic movement Hamas, whose election led the West and Israel to sever funds to the Palestinian Authority.

"Brother president, I appeal to you in the name of Islam ... to endorse dialogue and not a referendum," Haniya wrote in a four-page letter to Abbas.

"We must confront the imminent danger and unite in the face of the unjust siege," he said, referring to Western and Israeli financial restrictions imposed on Palestinians following Hamas's January election victory.

No legal basis

Haniya said the vote had "no legal and constitutional basis".

Instead of going to a vote, he said he wanted to continue negotiations based on the statehood proposal, drawn up by prisoners in an Israeli jail, with the goal of forming a unity government.

After initially calling the referendum earlier this week, Abbas gave Hamas a few more days to reconsider its position on a manifesto written by Palestinian prisoners in an Israeli jail.

"The Palestinian people in Jerusalem, the West Bank and Gaza Strip will be invited to take part in a referendum on the basis of the prisoners' document on Monday, July 31"

Palestinian official

"The Palestinian people in Jerusalem, the West Bank and Gaza Strip will be invited to take part in a referendum on the basis of the prisoners' document on Monday, July 31," a Palestinian official said.
   
He said the referendum would ask Palestinians one question: Do you agree with the prisoners' document or not?
   
Saeb Erekat, a top aide to Abbas, brushed aside Haniya's appeal.

He said: "This is illogical. Once there is a dispute, decision makers ask the people about their opinion. We hope that Mr. Haniyeh would not let us go to the referendum and accept the prisoners' initiative."