Israel's powerful Histadrut trade union confederation has called for an open-ended general strike beginning on Monday over what it calls the abuse of contract workers.
The union accuses the government of massively increasing its hiring of contract workers, who enjoy fewer rights and protections than civil service workers covered by collective bargaining agreements.
"This open-ended strike is intended to protest the second class status of hundreds of thousands of Israelis working in the public sector and some private companies," Histadrut spokesman Eyal Malma told AFP.
"The use of these workers, who do not benefit from the same social rights and are underpaid, has become a veritable epidemic to which we must put a stop," he added.
Malma said use of contract workers, who can be fired without notice, had grown so exponentially it was difficult to know how many people were now affected.
The government has urged the union to call off the strike, with Prime Minister Benjamin Netanyahu issuing a statement on Sunday saying "it is possible to find a solution."
But negotiations in recent days between Histadrut secretary general Ofer Eini and Finance Minister Yuval Steinitz ended without an agreement.
The union wants the government to offer a percentage of its current contract workers coverage under the civil service's collective bargaining agreement to ensure them the same rights and protections as their colleagues.
But the government has warned that it will not take any measures that could endanger Israel's economy, while saying it is open to increasing the minimum wage paid to contract workers and increasing their rights.
Without a last-minute agreement, the strike is set to begin at 6:00 am (0400 GMT) on Monday, paralysing ministries and local authorities, as well as public universities, hospitals and clinics.
Public transport will also grind to a halt along with operations at Ben Gurion international airport, Israeli banks, the Tel Aviv stock exchange and electricity and telecommunication companies, Malma said.