Thousands of anti-government protesters are standing their ground in the capital of Yemen, despite a deal that would see the president step down.
Protesters occupying a permanent camp in Sanaa say they don't trust President Ali Abdullah Saleh to keep his promise to leave office.
Mr Saleh agreed on Saturday to hand over power to his deputy within 30 days in exchange for immunity from prosecution.
Protesters say he must go immediately.
There were fresh demonstrations in Sanaa and in other parts of the country on Sunday.
Witnesses say the protesters in Sanaa are ringed by army units that defected to join and protect them. Uniformed soldiers were seen chanting alongside the demonstrators and flashing victory signs.
At least 130 people have died during two months of protests inspired by uprisings elsewhere in the Arab world.
Despite the protesters concerns, a coalition of seven opposition parties has generally accepted the deal, brokered by the Gulf Co-operation Council (GCC).
Protesters say the established opposition parties do not represent them.
"President Saleh has in the past agreed to initiatives and he went back on his word," said Khaled al-Ansi, a youth leader helping to organise the street protests.
"We have no reason to believe that he would not do this again."
Under the proposal, established opposition parties would first join President Saleh in a unity government.
The president would then submit his resignation, but to to a parliament that would be dominated by his own party, the ruling General People's Congress.
What happens if they reject his resignation is unclear. If approved, he would transfer power to his vice-president.
Opposition parties' spokesman Mohammed al-Sabri said the coalition would not discuss a unity government until after Mr Saleh stepped down.
"How could we form a government that gets sworn in by a president who has lost his legitimacy?" he said.
Mr Saleh has described the protests against him as an attempted "coup".
He told the BBC that al-Qaeda had infiltrated the opposition and the West would pay a price for ignoring what was happening. Protesters deny any links to al-Qaeda.
"You call on me from the US and Europe to hand over power," Mr Saleh said.
"Who shall I hand it over to? Those who are trying to make a coup? No. We will do it through ballot boxes and referendums. We'll invite international observers to monitor."
He said continuing protests could escalate the crisis.
Mr Saleh has promised not to renew his presidency in 2013 or hand over to his son. However, he has made - and broken - similar pledges in the past.
The US has urged all parties to "swiftly" implement a peaceful transfer of power.