|Essebsi, aged 84, described Ben Ali's former regime as "a gang of saboteurs" [EPA]
Beji Caid Essebsi, Tunisia's newly-appointed prime minister, has said he hopes to form a new interim government within two days.
He said the country was entering a new era and that the road ahead would be challenging.
"Today we are working with a popular revolution that does not have a framework," the prime minister said on Friday during a press conference in the capital, Tunis.
The prime minister's speech came a day after the interim president Fouad Mebazza said in a televised address that he and a caretaker government would stay in power until the election was held. Mebazza has been in charge since Ben Ali was toppled on January 14.
The president and a new transitional government to be formed by Essebsi will create a "public authority" that will cease functioning when the constituent assembly is elected, Mebazza said.
On Friday, the prime minister promised to form the new authority rapidly.
"I believe that a new Tunisian government, God Willing, will be formed in two days' time, with the approval of the president," Essebi said.
"All those that would like to leave, feel free to do so. But all those that wish to stay, the door is open."
Pledge to serve
Essebsi took over after Mohammed Ghannouchi resigned on Sunday, under pressure from protesters who condemned him as a hangover from the government that ruled under former president, Zine al-Abidine Ben Ali.
Essebsi has taken on the role of prime minister at the age of 84.
"As long as some years my life remain, I will continue to serve my country," he said, noting that his wife was not happy about his return to public life.
A lawyer by profession, he served as a minister under former President Habib Bourguiba, but has not been a member of government since Ben Ali took power in 1987.
He compared Tunisia's current political transition to that faced by the country when it became independent of French rule in 1956.
"Our country at that time had structures and institutions made it easy," he said.
"Today we are working with a popular revolution and does not have framework."
He said that the new government must maintain the principles and spirit of the uprising, a task which he called "a big responsibility and a big burden".
Essebsi described Ben Ali's former regime as "a gang of saboteurs".
"They have eaten up the gains, the flesh of the country," he said.