Thousands protest against presidents policies, accusing him of trying to stifle basic freedoms including union rights.
The crackdown on opponents of President Saied has sparked international criticism and fears of a return to autocracy.
The conference on fighting illicit financial transactions in Africa scheduled for mid-March has been delayed.
Hundreds of opposition supporters march through the streets to demand that President Kais Saied step down.
UGTT Secretary-General Noureddine Taboubi expressed support for jailed politicians and activists.
Eltaief, once a confidant of former President Ben Ali, and two key political activists were detained.
Racial tensions are spinning out of control as many sub-Saharan Africans prepare to leave the country.
If global powers are genuinely concerned about Saeids attacks on democracy, they should stop bankrolling his regime.
President Saied was condemned for his comments about illegal migrants from sub-Saharan Africa.
Demonstrators in Tunis marked 12 years since the Arab Spring revolution erupted across the region.