Ali Abdullah Saleh, Yeme's beleaguered president, is expected to address the nation as violence continues in the streets of the capital, Sanaa.
Sunday's speech will be Saleh's first since his surprise return to Yemen on Friday after three months of recuperating in Saudi Arabia.
Hours before the speech, tens of thousands of people gathered to demand that Saleh be tried for crimes committed during his decades-long rule.
Marching protesters, who set off from Change Square in the capital, chanted "Freedom! Freedom! The people want the butcher tried!"
At least one protester was killed and 14 injured by pro-Saleh forces as they attempted to reach Saba junction.
A freelance reporter, based in Sanaa, told Al Jazeera that the protesters "were marching down a main road" when they encountered members of Saleh's Republican Guard.
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"What I was told is that one soldier opened fire on them with a machine gun without any warning," he said.
"There was no tear gas. There was no water cannon. Just bullets were fired straight away."
In Taiz, Yemen's second largest city, three people were killed and three others wounded early on Sunday. Fighting erupted overnight between armed tribesmen who have thrown their support behind anti-government protesters and security forces loyal to Saleh.
Amid the violence, Saudi King Abdullah urged Yemenis to implement the Gulf Initiative by which Saleh would transfer power to his deputy.
"We see that the Gulf Initiative is still the exit to resolve the Yemeni crisis and prevent the situation (there) from getting worse," said Abdullah in a statement carried by state news agency SPA.
"We are sorry to see the violence that has left casualties and I call for self-retraint from all sides," he added.
Abuddlah's call comes after a specially bloody day, when government forces attacked unarmed demonstrators camped in Change Square and the headquarters of defected soldiers - killing 18 civilians and 11 soldiers, as well as wounding nearly 200 others.
At least 144 people have been killed in seven days of continued violence in Yemen as protesters seek to topple Saleh's government.
'Sick, vengeful soul'
The main military rival of Saleh accused him of being bent on driving the country into civil war and called on the international community to rein him in.
Major-General Ali Mohsen al-Ahmar issued a strongly worded statement on Saturday, calling Saleh a "sick, vengeful soul'' and comparing him to the Roman emperor Nero, burning down his own city.
Many Yemenis thought they had seen the last of Saleh when he flew to Saudi Arabia in June for medical treatment after a bomb explosion at his palace left him with severe burns.
His reappearance on Friday raised big questions over the future of the fractious Arabian Peninsula state.
|Violence has resumed in the capital, Sanaa [Reuters]
The UN Security Council, which include the US, China and Russia, issued a statement on Saturday calling on all sides to "reject violence, including against peaceful and unarmed civilians, and show maximum restraint."
The Security Council statement also "called on all parties to move forward urgently in an inclusive, orderly and Yemeni-led process of political transition".
A senior Saudi official told AFP news agency that Saleh had returned from Riyadh to put his house "in order" and "prepare for elections".
Saleh will "leave" after this, the official said without specifying whether he would leave Yemen altogether or only leave power.
Yemen's wealthy Gulf neighbours have been trying for months to persuade Saleh to accept a plan under which he would hand over power in return for a promise of immunity from prosecution.
Saleh had been involved in the negotiations, repeatedly promising to step down only to change his position at the last minute.
"I return to the nation carrying the dove of peace and the olive branch," Saleh was quoted as saying by state television on Friday.
He also called for a ceasefire.
However, the violent crackdown on anti-Saleh protesters by pro-Saleh forces have left many Yemenis skeptical of his intentions.