Protesters demanded a swift transfer of power from Ali Abdullah Saleh as his deputy said the veteran Yemeni president would return within days after surgery in Riyadh for blast injuries.
EU foreign policy chief Catherine Ashton on Monday urged Saleh to act "in the best interest of his people" while the White House called for an "immediate transition."
"His excellency is making a strong recovery and will return home in the coming days," Vice President Abdrabuh Mansur Hadi said at a meeting of the ruling General People's Congress, quoted by the official Saba news agency.
In Sanaa, a fragile truce held despite a deadly sniper attack on loyalists of a powerful tribal chief blamed for Friday's bomb attack which wounded Saleh as he prayed inside a mosque in his compound.
As Saleh, 69, recuperated in a Riyadh military hospital, a committee of youth activists that has been a key player behind the four-month uprising against his nearly 33 years of iron-fisted rule called for a quick transfer of power.
The committee urged "all national and political forces to begin by forming an interim presidential council."
It also called for a "government of technocrats" to lead the transition.
Tens of thousands of people took to the streets of Yemen's capital on Sunday to cheer what they saw as the end of Saleh's regime.
Impoverished Yemen's wealthy Gulf neighbours, who have been trying to broker a peaceful transition for months, said their proposal for Saleh to hand over power in return for the promise of immunity from prosecution remained the "most suitable solution."
"The council member-states could activate (the proposal) and follow up on its implementation, if Yemen parties agree on it," said Gulf Cooperation Council chief Abdullatif al-Zayani, whose mediation efforts since April have repeatedly run into objections from Saleh.
The EU foreign policy chief recalled that the Yemeni president had almost signed the Gulf proposals on three occasions, and said: "He knows perfectly well what he needs to do for his people."
"I trust he will do that," Ashton added.
Washington also reiterated its support for the Gulf plan.
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"An immediate transition is in the best interests of the people," White House spokesman Jay Carney told reporters.
Britain on Monday confirmed the deployment of "military assets" near Yemen but did not verify reports that ships were on standby in the Gulf to evacuate its nationals.
"As part of routine deployment UK military assets are in the region, although we are not prepared to comment further on their exact operational tasking," a Ministry of Defence (MoD) spokesman said.
Around 80 marines were on board naval support ship RFA Fort Victoria, according to the BBC, while Sky News reported that the RFA Argus was also in the area.
The parliamentary opposition in Yemen has vowed to prevent Saleh's return to power, following a crackdown on anti-regime protests that has killed at least 200 people.
"We will work with all our strength to prevent his return," parliamentary opposition spokesman Mohammed Qahtan told AFP. "We see this as the beginning of the end of this tyrannical and corrupt regime."
The president underwent two "successful" operations on Sunday, a Saudi official in Riyadh told AFP.
"The first was to remove a piece of shrapnel from his chest, and the second was neurosurgery to his neck.
"The next procedure will be for cosmetic surgical purposes. The period of convalescence is two weeks, after which he will return to Sanaa," the official said on condition of anonymity.
The embattled president, in power in Sanaa since 1978, had flown to Riyadh on a Saudi medical aircraft late on Saturday, while a second plane carried members of his family.
Saudi Arabia said on Monday it had received Saleh at his request and out of religious duty.
It also said it hoped the Yemeni parties would sign up to the Gulf transition plan.
Saleh's government has blamed the bomb attack on dissident tribal leader Sheikh Sadiq al-Ahmar, whose fighters have been battling government forces in Sanaa since the Gulf plan crumbled last month.
Sheikh Sadiq's office said on Sunday that he had agreed to a conditional truce at the request of the vice president under which he would withdraw his forces from public buildings which they seized during battles that killed nearly 140 people.
But even as residents reported a lull in fighting in Sanaa, snipers shot dead three of Sheikh Sadiq's supporters in the capital on Monday, a tribal source said, blaming government troops.
Saleh's eldest son Ahmed, commander of the elite Republican Guard, has remained in Yemen. The opposition says Ahmed was already preparing to take over from his father before the popular uprising.