BUDAPEST - Tens of thousands of Hungarians protested in central Budapest on Sunday against the centre-right government, demanding more transparent legislation and protection for the country's free market.

Protesters, organised mainly through Facebook, came from a loose alliance of liberal intellectuals and unions, which has grown in recent months alongside deep discontent with all political parties.

Hungary's ruling Fidesz party has lost more than a million voters since it won a two-thirds majority in parliament last year, alienating them with measures many feel have been forced on them after little or no consultation.

The government has said it has done more than previous administrations to listen to voters.

To reduce public debt and the budget deficit, Fidesz grabbed about $15 billion worth of private pension fund assets. It plans a series of tax hikes and austerity measures next year to contain spending. Fidesz has restricted the powers of the top court, and has rewritten the constitution.  

Earlier this year it passed a controversial law on the media and it is about to change the electoral system.  

"We have come together to show again after 55 years that we stand up for our rights, for democracy," Peter Juhasz, spokesman for the organisers, told the crowd of about 25,000.

"Many people would like to talk for the citizens, but it is we citizens who have to show that we don't like the system," said Juhasz.

Protesters said they wanted to show the government that its practice of legislating without consultation was unacceptable.

"It is very important that we give a signal," said Andras Forgach, a 59-year-old writer and dramatist from Budapest.  

"These demonstrations allow new faces to appear. It's like a casting, and we are the ones who do the casting... Something is brewing here, a formation that might have a shot at the next elections," he said.

Hungary holds its next parliamentary elections in 2014.