SANAA (Reuters) - A Gulf plan to ease Yemeni President Ali Abdullah Saleh out of power has been modified to allow him not sign it as president, the opposition said on Friday, a condition that nearly derailed the deal last week.
Saleh, who first indicated he would sign the deal devised by the Gulf Cooperation Council (GCC), refused to put his name to it last week, saying he should do so as party leader, not president.
The plan requires the Yemeni leader, until recently backed by Saudi Arabia and the United States as a bulwark against al Qaeda and regional instability, to resign 30 days after signing.
Critics saw the move as a clear sign Saleh, a shrewd political survivor, had no intention of stepping down quickly.
Sceptical opposition leaders said on Friday it appeared the GCC had acceded to demands by the ruling party.
"This evening we received a new agreement plan and were surprised to see it had been amended according to President Saleh's demand," said an opposition leader who asked not to be identified.
"They changed the title of the deal from 'Accord between the opposition and the government' to 'Accord between the General People's Congress (ruling party) and its allies and the Joint Meeting Parties bloc (opposition coalition)'," he told Reuters.
Gulf Arab states including Saudi Arabia, Yemen's neighbour, are eager to see peace return to Yemen, a poor state struggling to deal with internal rebellion and home to al Qaeda's active Arabian Peninsula branch.
Many worry that Yemen that could quickly spiral into further violence -- half of its 23 million people own a gun.
Protests for and against Saleh attracted large crowds in the capital on Friday. In cities throughout Yemen, anti-Saleh protesters were out in force.
"Oh God, topple the tyrant of Yemen," they shouted.
Saleh has defied three months of protests and on Friday called his opponents "outlaws" and "forces of terror."
"Yes to constitutional legitimacy, not to chaos, no to revenge plans ... I assure you we will stand together, firm, like the mountains of Ayban and Shamsan," he told the crowds.
U.N. Secretary General Ban Ki-moon vowed to continue pressing for change in Yemen, but sounded a note of exasperation at the slow progress.
"It is unfortunate and frustrating that all these agreements which were presented by the GCC and the international community have not been fully accepted and agreed and implemented."
Yemeni opposition leaders told Reuters they would meet on Saturday to discuss how to respond to the modified deal.
A GCC source told Reuters Gulf foreign ministers might try to meet in Riyadh on Sunday to discuss the crisis.
Anti-Saleh protesters, furious about rampant corruption and poverty, keen to see Saleh held to account and fearful of being sold out by opposition politicians, were growing impatient.
"We'll use other means to force him out," said one, Fahed Mansour. "We'll escalate a general strike and stop movement in every city. He can't hold out against our revolution forever."
As talks stall, Yemen's economic and fuel crisis worsens. Armed tribesmen have blocked shipments from oil- and gas-producing Maarib province.
The government and opposition accuse each other of backing the tribes. A shipping source said the cash-strapped government was losing $3 million a day from the loss of its Maarib exports.
Trucks and cars wait in long queues in the hope of receiving a fuel ration. Electricity is often cut for up to 10 hours.
Additional reporting by Asma Alsharif in Riyadh; Writing by Erika Solomon; Editing by Andrew Dobbie