Mayor Bill de Blasio visited Mott Haven Thursday to sign a new law making it difficult for landlords to force tenants out of rent-stabilized apartments.

The legislation outlaws several tactics the mayor deemed "unscrupulous."

"Landlords using cash offers to get rent-regulated tenants to move so the landlords can charge sky-high rents...that will end now," de Blasio said at the event. "Those days are over."

The new rules ban landlords from making threats against tenants, harassing tenants at their workplaces or at odd hours of the night, and from making buyout offers without informing tenants that they have a right to remain in their apartments.

"We have recognized it is a problem, and now it is fully illegal," said Councilman Jumaane Williams. "Now it is backed by fines that you can no longer do this. You can no longer harass people out of their homes."

Officials said the maximum fine for a first-offense can be up to $10,000.