Image caption Mohammed Ghannouchi was seen as too closely linked to the old regime 
 
 Tunisian Prime Minister Mohammed Ghannouchi has announced on state TV that he is resigning - a key demand of demonstrators. 
 
 He was speaking at a news conference in Tunis, after making a lengthy speech defending his record in government. 
 
 Mr Ghannouchi is seen as being too close to former President Zine al-Abidine Ben Ali, who was toppled in an uprising last month. 
 
 Mr Ghannouchi, 69, had served under Mr Ben Ali since 1989. 
 
 "After having taken more than one week of thinking, I became convinced, and my family shared my conviction, and decided to resign. It is not fleeing my responsibilities; I have been shouldering my responsibilities since 14 January [when Mr Ben Ali fled]," he said. 
 
 "I am not ready to be the person who takes decisions that would end up causing casualties," he added. 
 
 "This resignation will serve Tunisia, and the revolution and the future of Tunisia," he added. 
 
 At the scene It is exactly what the protesters had been demanding. Mohammed Ghannouchi, had served under the country's old dictatorship, and as far as they were concerned, until he went, their revolution was unfinished. The question now is whether this resignation will be enough to quell the violence. As the news has spread, people have been taking to the streets, chanting and singing of victory. 
 
 Within hours a replacement was named for Mr Ghannouchi - Beji Caid-Essebsi, 84, who served as foreign minister in the government of the late President Habib Bourguiba. 
 
 Earlier in the day, police in Tunis fired tear gas and warning shots to disperse the latest demonstration calling for a new government and a new constitution on a third day of violence. 
 
 Huge protests 
 
 On Friday and Saturday, anti-government protesters held huge rallies calling for Mr Ghannouchi's resignation. 
 
 At least three people were killed in clashes between hundreds of demonstrators and security forces in Tunis on Saturday. 
 
 Tunisia's government had insisted it was introducing reforms as fast as it could, and that it was planning to hold elections by July. 
 
 Media playback is unsupported on your device Media caption The BBC's Paul Moss in Tunis: "Police are giving protesters merciless beatings" 
 
 But those promises did not seem to satisfy the protesters, correspondents say. 
 
 The fall of Mr Ben Ali after 23 years in power sparked similar uprisings in the Arab world, including one that led to the downfall of long-time Egyptian President Hosni Mubarak on 11 February and another under way in Libya. 
 
 The trigger for the protests in Tunisia was a desperate act by a young unemployed man on 17 December 2010. 
 
 Mohammed Bouazizi set fire to himself when officials in his town prevented him from selling vegetables on the streets of Sidi Bouzid without permission. ||||| Tunisia's interim president chose a former government minister as a new prime minister on Sunday, appealing for a return to calm following new violent protests that have been hobbling this North African country since the ouster of its long-time autocratic leader. 
 
 In this undated photo is the newly named Tunisian Prime Minister Beji Caid-Essebsi. Tunisia's interim president has named former government minister Beji Caid-Essebsi as the country's new prime minister... (Associated Press) 
 
 A Tunisian riot police officer kicks a anti-government protester during a demonstration, in Tunis, Sunday Feb. 27, 2011. Tunisia's embattled prime minister said Sunday that he will resign, bowing to a... (Associated Press) 
 
 Anti-government protesters lay on the ground after being apprehended by Tunisian soldier during a demonstration, in Tunis, Sunday Feb. 27, 2011. Tunisia's embattled prime minister said Sunday that he... (Associated Press) 
 
 Anti-government protesters are seen behind a barricade during a demonstration, in Tunis, Sunday, Feb. 27, 2011. Tunisia's embattled prime minister said Sunday that he will resign, bowing to a key demand... (Associated Press) 
 
 A Tunisian riot police officer escorts away an anti-government protester during a demonstration, in Tunis, Sunday Feb. 27, 2011. Tunisia's embattled prime minister said Sunday that he will resign, bowing... (Associated Press) 
 
 Tear gas smoke is seen during a anti government protest, in Tunis, Sunday Feb. 27, 2011. Tunisia's embattled prime minister said Sunday that he will resign, bowing to a key demand of protesters after... (Associated Press) 
 
 Tunisia'S former Prime Minister Mohamed Ghannouchi, center, is seen with Tunisia'S Interior Minister Farhat Rajhi, left, and Gen. Rachid Ammar, right, after his resignation's annouNcement in Tunis, Sunday... (Associated Press) 
 
 Tunisian President Fouad Mebazaa announces the new Tunisian Prime Minister during a press conference, in Tunis, Sunday Feb. 27, 2011. Mebazaa named former government minister Beji Caid-Essebsi as prime... (Associated Press) 
 
 Tunisian riot police officers arrest antigovernment protesters during a demonstration, in Tunis, Sunday Freb. 27, 2011. Tunisia's embattled prime minister said Sunday that he will resign, bowing to a... (Associated Press) 
 
 Tunisian riot police officers are seen during a antigovernment protest, in Tunis, Sunday Feb. 27, 2011. Tunisia's embattled prime minister said Sunday that he will resign, bowing to a key demand of protesters... (Associated Press) 
 
 Tunisian Prime Minister Mohamed Ghannouchi gestures as he announces his resignation during a press conference in Tunis, Sunday Feb. 27, 2011. Tunisia's embattled prime minister said Sunday that he will... (Associated Press) 
 
 Tear gas smoke is seen during an anti-government protest, in Tunis, Sunday Feb. 27, 2011. Tunisia's embattled prime minister said Sunday that he will resign, bowing to a key demand of protesters after... (Associated Press) 
 
 Tunisian former Prime Minister Mohamed Ghannouchi, right, hugs the Tunisian Interior Minister Farhat Rajhi, left, after his resignation's annoucement in Tunis, Sunday Freb. 27, 2011. Ghannouchi's announcement... (Associated Press) 
 
 Beji Caid-Essebsi will replace Mohammed Ghannouchi, who resigned earlier Sunday after becoming a major irritant to Tunisians behind the so-called "Jasmine Revolution" that toppled autocratic President Zine El Abidine Ben Ali last month and sparked a wave of upheaval in the Arab world. 
 
 The caretaker president, Fouad Mebazaa, made the appointment later Sunday. 
 
 As Ben Ali's prime minister for 11 years, Ghannouchi became the emblem of an entrenched old guard that many Tunisians feared were hijacking their revolution. 
 
 It was not immediately clear how much the shake-up would mollify the protesters in Tunisia, at a time when its leaders are attempting to rebuild its tourism industry and cope with an influx of Tunisians and others fleeing from violence in neighboring Libya. 
 
 The change in the government's leadership follows renewed street protests. Officials said that at least five people have died in violent street protests since Friday. 
 
 Ghannouchi had previously vowed to stay on to guide Tunisia until elections could be organized this summer. 
 
 As he stepped down, Ghannouchi sought to take the high ground. 
 
 "This (resignation) is not a flight from my responsibilities, but to open the way for another prime minister who _ I hope _ will have more margin for action than I have had, to give hope to the Tunisian people," he said. 
 
 "I am not ready to be the man of repression, and I will never be," Ghannouchi said, warning that unspecified forces appeared to be swelling to try to quash the move toward democracy. 
 
 Caid-Essebsi is an elderly statesman and lawyer who served in government posts under the Tunisia's two longtime leaders since it gained independence from France in 1956: Habib Bourguiba and Ben Ali. 
 
 Ben Ali was driven from power on Jan. 14 and fled to Saudi Arabia following weeks of a deadly popular uprising that has fanned similar upheaval across the Arab world. 
 
 Some Tunisians believe that Ben Ali loyalists in the country have sought to sow discord and discredit the movement that brought the former authoritarian leader down. 
 
 "There needs to be reconciliation among all Tunisians to show the world that Tunisia is a civilized country," Ghannouchi said. "My resignation will help create this new atmosphere." 
 
 The Interior Ministry, in a statement Saturday, blamed "provocateurs" for fomenting violence in otherwise peaceful rallies and for allegedly using young people as human shields in renewed demonstrations. 
 
 On Saturday, police and troops backed by tanks used tear gas to disperse hundreds of youths protesting against the caretaker government. Officers were seen chasing some youths through town after the rally ended. 
 
 Authorities then ordered a temporarily ban on vehicle and pedestrian traffic on the capital's central Bourguiba Avenue until midnight Sunday _ the first of its kind since Ben Ali's downfall. 
 
 On Friday, police fired tear gas and warning shots as violence erupted alongside a sit-in that drew tens of thousands of protesters near the seat of the interim government. 
 
 Officials said nearly 200 people were arrested over the last two days.
– Interim Tunisian President Foued Mebazaa has appointed a new prime minister following the resignation of Mohammed Ghannouchi, who bowed to protesters' demands and stepped down yesterday, the BBC reports. Former foreign minister Beji Caid-Essebsi will take Ghannouchi's place, although it's not clear whether the appointment will be enough to mollify the protesters who have returned to the streets of Tunis in large numbers, AP notes. Osama bin Laden's deputy Ayman al-Zawahri has recorded a message urging Tunisians and Egyptians to rise up against their interim governments.