By Tarek Amara and Lin Noueihed
TUNIS (Reuters) - The Tunisian government ditched loyalists to its ousted president on Thursday -- a move which won backing from the powerful labour union and could help defuse protests which have inspired people across the Middle East.
Prime Minister Mohamed Ghannouchi, who retained his job, said 12 ministers would be replaced, purging the interim government of members of the former ruling party including the interior, defence and foreign ministers.
"This government is a transitional, interim government that will remain until it completes its mission of taking the country to democracy," Ghannouchi said in a live television address.
Weeks of violent protests by Tunisians angered by poverty, repression and corruption forced President Zine al-Abidine Ben Ali to flee to Saudi Arabia on January 14 after 23 years in power.
But they had been angered after an interim government led by Ghannouchi had retained many former Ben Ali loyalists.
The purge is unlikely to fully quell protests in Tunisia, some of which are spontaneous and others more organised.
After the prime minister's television address, chants of "bread, water but no Ghannouchi" broke out among protesters who had launched a sit-in outside his office to demand he resign.
"We reject Ghannouchi totally. We were surprised to see him announce the government," said protester Mohammed Fadel. "Since he did not fight corruption under Ben Ali, he is an accomplice."
But the move would nonetheless provide greater legitimacy to the interim government, which had struggled to impose order after Ben Ali fled.
Earlier on Thursday, thousands of demonstrators thronged Bourguiba Avenue, the main boulevard in the capital Tunis, demanding that the government resign.
They also broke through police lines outside the prime minister's office, where hundreds of demonstrators had pledged to camp out until the government resigned.
The purge replaced members of Ben Ali's former ruling RCD party with ministers who Ghannouchi said were chosen for their high levels of experience and qualifications.
He also promised the new government -- agreed after talks with all political parties and civil society groups -- would lead the country into its first free elections, to be organised by an independent body and monitored by international observers.
The powerful UGTT labour union, which has a large membership and played an important role in organising the protests, will not join the new government itself but would approve the new lineup, a union source told Reuters.
TUNISIA INSPIRES PROTESTS ACROSS MIDEAST
Tunisia's uprising has electrified Arabs across the Middle East and North Africa, where many countries share the complaints of poor living standards and authoritarian rule.
Inspired by Tunisia's example, thousands of Egyptians have taken to the streets to demand an end to President Hosni Mubarak's 30-year rule.
Protests have also spread to Yemen, where thousands took to the streets to demand a change of government.
In addition to the cabinet reshuffle, Tunisia is aiming to set up a council of "wise men" to guide the country to democracy from the authoritarian state run by Ben Ali.
Veteran politician Ahmed Mestiri, a prominent figure during the era of Tunisia's independence leader Habib Bourguiba, said he hoped to head the council.
"The council would protect the revolt that broke out spontaneously. The time has come for the process to be structured," Mestiri, 80, said in an interview on Wednesday.
In the unrest that brought down Ben Ali, the United Nations has said that 117 died, including 70 killed by gunfire.
Amnesty International that it had established that security forces used disproportionate force to disperse protesters and in some cases fired on fleeing protesters and bystanders.
The rights group said doctors' testimonies seen by its researchers show some protesters were shot from behind, indicating they were fleeing. Others were killed by single shots to the chest or head, suggesting deliberate intent to kill.
"This shocking evidence confirms that the Tunisian security forces were using lethal methods to quell discontent and to deter protesters," said Hassiba Hadj Sahraoui, Deputy Director of Amnesty International's Middle East North Africa Programme.
A U.N. human rights team begins work in Tunisia later on Thursday. The 8-strong team will investigate past violations and advise the interim government on justice and reforms.
Tunisia's interim government had begun to compensate the families of those killed or wounded in the protests, the state news agency said.
(Writing by Myra MacDonald; Editing by Maria Golovnina.)