ATHENS (Reuters) - Greek Prime Minister Antonis Samaras moved to defuse a political crisis over the government’s abrupt closure of state broadcaster ERT that prompted a nationwide strike on Thursday and brought thousands into the streets in protest.

Samaras, who has branded defenders of ERT hypocrites, invited two left-wing junior coalition parties opposed to the shutdown to talks next Monday, his office said, seeking to avert political instability in the bailed-out euro zone country.

A senior government official said the conservative prime minister was open to discussing their proposals and a compromise was likely, though he did not intend to back down from closing ERT and relaunching a smaller, more efficient entity.

“I believe there is scope for compromise and we will not go to new elections,” the official told Reuters.

The partners, who want ERT switched back on immediately, welcomed the meeting but kept up a critical broadside that has pushed Greece into its most serious political crisis since the uneasy right-left coalition came to power a year ago.

“The country doesn’t need elections, they would be a colossal mistake, but PASOK is not afraid of them,” Socialist PASOK chief Evangelos Venizelos said. “We support a radical restructuring of ERT, but not with blacked-out screens.”

An uneasy alliance of parties that have little in common apart from the desire to keep Greece in the euro zone and hooked to an international bailout, the coalition has regularly bickered over austerity policies and immigration issues.

But the ferocity of the public clash between Samaras, who has vowed to transform Greece from “a real Jurassic Park” into a modern economy, and his allies has raised doubts about whether a face-saving formula can be found.

“The country is on a knife’s edge,” a coalition source said.

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“Either there’s a solution in a week or it’s elections,” conservative newspaper Kathimerini said on its front page.

Opinion polls show both PASOK and Democratic Left would struggle to keep their share of parliamentary seats if elections were held now. Samaras’s New Democracy has widened its lead over the hard left Syriza, but would fall well short of the majority needed to govern alone without smaller allies.

In a show of support, the European Broadcasting Union (EBU) worked around ERT’s shut down, putting the Greek broadcaster back on air late on Thursday, enabling Greek satellite subscribers to watch the station’s news channel on television.

Before the move, ERT’s output was only available via a live stream on the EBU website.

ONLY OPTION?

The ERT crisis erupted a day after the government failed to sell natural gas firm DEPA and was cut to emerging market status by equity index provider MSCI, pushing Greek bond yields to the biggest rise in the euro zone market this week.

Ten-year borrowing costs are back above 10 percent, their highest since early May, prompting analysts to suggest Athens will struggle to return to the bond market next year as planned.

Athens has described the 75-year-old broadcaster’s shutdown as a temporary measure pending the relaunch of a slimmed-down station. About 2,600 employees are to lose to their jobs, though the government has promised to compensate them.

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Late on Thursday, the finance ministry also asked the anti-corruption prosecutor to look into any possible wrongdoing at ERT over the procurement of equipment, production assignments and work contracts.

A senior government official said Athens was under pressure to show visiting EU and IMF inspectors that it had a plan to fire 2,000 state workers as required, and the ERT shutdown was the only option available to meet the goal.

Senior euro zone officials meet later on Thursday to discuss unlocking the next 3.3 billion euros ($4.4 billion) of loans.

City buses did not run in Athens and train services were halted across the country after Greece’s two biggest labor unions staged a 24-hour strike.

More than 13,000 protesters - including unemployed youths and leftists - gathered outside ERT’s headquarters waving flags and holding banners reading “Fire Samaras, not ERT workers!”

“Samaras can’t tell us what to watch or not. This isn’t about ERT or about its workers any more, it’s about democracy and freedom of speech,” said Thanos Lykourias, 30, an office worker who earns 800 euros ($1,100) a month and lives with his mother.

Many Greeks regard ERT as a wasteful source of patronage jobs for political parties. But the abruptness with which the government pulled the plug - blacking out screens with newscasters cut off in mid-sentence - was a shock.

An indefinite strike by a journalists’ union prevented some newspapers appearing and forced private broadcasters to air reruns of sitcoms and soap operas instead of the news.

But there was little sign of private sector workers joining the stoppage. City streets were full of traffic, supermarkets were open and cafes were bustling.

Data released on Thursday showed unemployment climbed to an all-time high of 27.4 percent in the first quarter of 2013 after more than 850,000 jobs, most in the private sector, were wiped out since the beginning of Greece’s six-year recession.