ATHENS, Greece (AP) -- Greece's main civil servants union on Thursday vowed to file law suits against the Socialist government over a (euro) 50 billion privatization program, describing it as an act of "national treason," as part of a fall campaign to disrupt revenue collection.
Ilias Iliopoulos, general secretary of the powerful ADEDY union told The Associated Press that a final decision was expected at a union meeting on Sept. 22.
The once pro-Socialist union has already outlined plans to stage a campaign of disruptive strikes against austerity measures in the fall -- threatening the country's already-fragile revenue collection.
"For us this (privatization) is an act of national treason, and those who attempt it will face the consequences accordingly," Iliopoulos said. "We will use all means at our disposal to, of course, hopefully overturn the government, but mainly to file law suits against those who sign these (privatization) agreements."
He said the plan is to send a message to "these so-called investors, who want to snatch our national wealth at a humiliating price. They can do whatever else they like with their money, but this will never happen."
The government has faced down months of often-violent protests as it pushed through successive waves of cost-cutting measures that has seen unemployment rise to record levels.
The jobless rate reached 16.6 percent in May -- a new high -- from 15.8 percent a month earlier, according to figures reported Thursday by Greece's Statistical Authority.
The agency said 220,534 had lost their jobs in the last year, with the number of people out of work reaching 822,719 in the country of about 11 million people.
European leaders agreed last month on a second bailout worth (euro) 109 billion ($155 billion) for Greece, which was granted its first, equivalent rescue from international creditors last year.
In return, Greece promised to drastically speed up its privatization program -- to stabilize the national debt -- and impose strict austerity measures, increasing taxes and cutting public sector pay and pensions.
Stuck in recession for a third year, Greece is struggling to meet its deficit reduction targets, while the sell-off of state-owned companies remains threatened by plunging stock prices that hit their lowest level in 14 years this week.
Iliopoulos said his union would change strike tactics after the summer, as part of a renewed anti-government campaign.
"The strike might be confined to one region one day, followed by another that will affect a certain profession, and then joined nationally by civil servants the day after that," he said. "Of course this means that there will be negative consequences for revenues, because employees will not be present to receive payments."
On Wednesday, the government warned it would not tolerate any attempt to disrupt tax payments, renewing a threat to review decades-old job guarantees for state-paid workers.
"This is totally irresponsible and against the public interest," government spokesman Ilias Mosialos told private Skai television. "We have 800,000 public servants, that's roughly the same number of people who are unemployed. (Civil service) job rights are guaranteed by the constitution and, but undermining the public interest is not."
Last month, the Greek Inspector of Public Administration reported major delays in tax collection, up to 94 percent of revenue targets by some local tax offices -- accusing some employees of carrying out an informal work-to-rule protest.
The Greek Federation of Tax Office Employees has called a 48-hour strike on August 23 and 24 to protest pay cuts.
Elena Becatoros in Athens contributed.