The city's rent regulations expired late Monday when state lawmakers failed to reach an agreement extending the rules before a midnight deadline. 

The rent stabilization law protects 2 million New Yorkers living in rent-stabilized apartments from out-of-control price increases. It also prevents landlords from evicting tenants when their leases expire, and is seen by many as a key protection to affordable housing. 

Gov. Andrew Cuomo is meanwhile sending a strong message to landlords, saying in part, "While the Legislature needs to act immediately, New York tenants should know that this state government will have zero tolerance for landlords that seek to exploit those who live in rent-regulated units." 

The year's legislative session ends Wednesday, and Cuomo is promising to call lawmakers back into session if they don't strike a deal on rent rules. 

The law expired four years ago when it came up for renewal, but an extension passed a few days later.