Michelle Bachelet has taken over the presidency of Chile in a ceremony loaded with symbolism, after promising to stick to her tax-and-spend campaign pledges, despite a sharp economic slowdown.

Returning to Chile's top job after a spell with the United Nations, Bachelet heads a coalition that ranges from moderate leftists to communists.

The new president says she wants to address social inequality by overhauling education and healthcare, funded by tax reforms.

Bachelet's swearing-in at the port city of Valparaiso, the seat of Chile's Congress, was attended by presidents from around the region, with the notable exception of Venezuela's Nicolas Maduro, who was due to come but apparently cancelled at the last minute, the Reuters news agency reported.

"[The transfer of power was] very democratic, very moderate, as it should be," said Colombia's centre-right President Juan Manuel Santos, frontrunner in his country's upcoming presidential election.

"And even something unusual to Latin America: no speeches. It is a lesson for the rest of the countries in Latin America."

Uruguay's President Jose Mujica, a former fighter known for backing progressive social policies in his country, gave a warning to new politicians.

"Chile depends on you all, whatever colour you have, take care of what you have. Keep it. It's very easy to lose," Mujica said.

READ MORE: Bachelet sworn in again as Chile's president