The threat of a strike by Las Vegas casino workers diminished as the union representing 50,000 bar staff, waiters, cooks, housekeepers and porters reached new five-year contract deals with the two biggest casino groups, MGM Resorts and Caesars Entertainment.

MGM Resorts and Caesars operate 19 Las Vegas properties between them, employing 26,000 of the 50,000 union members authorised to strike.

The Culinary Workers Union (CWU) remains in negotiations with 15 casino properties in downtown Las Vegas and on the Strip, including the Four Season, Stratosphere, Tropicana and Westgate.

Union leaders said they are seeking the same terms reached with MGM and Caesars. However, details have yet to be disclosed.

The union had sought a 4% pay increase and improvements in benefits along with guarantees on jobs in face of automation and tougher action against sexual harassment of staff.

A union spokeswoman said: “The agreements have historic language regarding technology and automation, and safety [including] sexual harassment.”

Geoconda Arguella-Kline, CWU secretary-treasurer, said: “This contract includes the strongest and most comprehensive language on immigration, sexual harassment and safety in the history of any union in the US.”