KABUL -ATHENS - Greek political parties and unions battled Wednesday to reverse the shock shutdown of state broadcaster ERT as a storm erupted over the government's latest austerity cutback.

ERT's television and radio stations were abruptly taken off the air on Tuesday and its 2,700 staff suspended after the conservative-led government branded the broadcaster a "haven of public waste".

The shutdown caused uproar in Greece, where journalists were staging a 24-hour strike on Wednesday while defiant staff staged sit-ins at ERT offices in Athens and the second city of Thessaloniki. "This is a coup d'etat," said Alexis Tsipras, leader of the main opposition party Syriza.

The move by the coalition government of conservative Prime Minister Antonis Samaras is part of sweeping austerity measures demanded by the debt-laden country's international lenders in return for a massive bailout.

Greece is caught in a six-year recession which austerity critics say has been exacerbated by successive pay and pension cuts imposed at the behest of its EU-IMF creditors. Unemployment is steadily rising and now exceeds 26 percent, with half of young people out of work. "We cannot tolerate havens of non-transparency and public waste," government spokesman Simos Kedikoglou told reporters on Tuesday as he announced the closure.

"ERT is a case of an exceptional lack of transparency and incredible extravagance. This ends now," said Kedikoglou, himself a former journalist at the organisation.

Employees at the station, stunned by the sudden loss of their jobs, were defiantly transmitting rogue broadcasts on the Internet on Wednesday, vowing to resist the shutdown.

"We are not leaving the building," Panagiotis Kalfayiannis, the head of ERT's main union, told AFP.

"We are going to Greek and European justice. Even if they want to destroy democracy, rules still apply and I am going to fight."Protest rallies have been called in support of ERT staff and unions are planning a general strike, reportedly for Thursday.

Thousands of people rushed to ERT's main headquarters in Athens and its Thessaloniki offices on Tuesday to show their support for the broadcaster.

The European Union said it did not question the government decision but said public broadcasting was "an integral part of European democracy".

Media observers acknowledge that ERT has a long history of mismanagement and heavy-handed political meddling, but say the Samaras administration was not free of blame.

Recent controversial decisions include the appointment of a former deputy minister's daughter as a show host, and the ousting of two journalists who had criticised the public order minister on air.

"This is deep hypocrisy," veteran journalist Yiannis Tzannetakos told Sto Kokkino radio station. "The responsibilities rest with various governments which appointed the management of ERT."

Messages of support for the broadcaster have poured in from the Greek diaspora -- for whom ERT is a vital link to the homeland.

The head of the Orthodox Church of Greece, Archbishop Ieronymos, said ERT staff were being "sacrificed" to pay for decades of wasteful administration.

"Healing an organisation is one thing, but killing it abruptly and violently is totally different," he said.

The government described ERT as a huge drain on public coffers and said it would reopen at a later stage under a new format and with considerably fewer employees.

It said all 2,655 current staff would be compensated and allowed to reapply for a job at the revamped organisation.

A bill on the reform of public broadcasting was due to be considered at a cabinet meeting on Wednesday.

But junior coalition partners Pasok voiced deep opposition to the closure, and Tsipras said he plans to ask President Carolos Papoulias to refuse to sign the order for ERT's dissolution.

"We absolutely disagree with the government's particular decisions and management," the socialist party said. "We will not vote in favour of the law validating this legislative act."

Kedikoglou's announcement came after months of work stoppages by ERT employees in protest at plans to restructure the broadcaster called for by Greece's troika of international creditors.

Athens has pledged to cut 4,000 state-sector jobs this year and another 11,000 in 2014 to keep drawing rescue loans under its massive bailout from the EU and the IMF.

"They don't want to keep anything in public hands: hospitals, schools, everything is going, they are barbarians," protested retired French teacher Therese Alatsi.