An estimated half-million Romanians took to the street in another night of protests on Sunday, with many calling on the government to quit even after it scrapped the corruption legislation that sparked the week of public outrage.

Prime Minister Sorin Grindeanu stood firm, however, saying his government, which has barely been in office a month, would not resign.

The last six nights of noisy protests thronging cities and towns around the country have been the biggest outpouring of public anger since 1989.

The object of public anger is an emergency decree passed on Tuesday which critics at home and abroad feared marked an alarming retreat in the battle against corruption, long the scourge of the EU's second-poorest country.

Grindeanu's Cabinet on Sunday repealed the decree, but this failed to assuage protesters, many of them chanting "Resign! Resign!" as they waved flags, brandished signs and blew whistles.

"We want justice. ... The government will still try something (with the decree)," said Emma, 24, one of between 200,000 and 300,000 people media estimated had gathered in downtown Bucharest

"They are liars and bad people," said her friend Nicole, 25. "The government has to fall. ... We are going to come back here every night."

The decree, which had been scheduled to enter into force on Feb 10, was to make abuse of power a crime only punishable by jail if the sums involved exceeded $47,500.

The government still also aims, via a separate decree to be reviewed by Parliament, to free some 2,500 people from prison serving sentences of less than five years.

Grindeanu's Social Democrats, or PSD, have argued the measures were meant to bring penal law into line with the Constitution and reduce overcrowding in prisons.

But critics see the moves as a transparent attempt to let off the many PSD officials and lawmakers who have been ensnared in a major anti-corruption drive of recent years.