The hack led to a six-day fuel pipeline shutdown.
U.S. President Joe Biden repeatedly warned the gangs and major host country Russia.
Multiple ransomware groups claimed they were shutting down or scaling back operations on Friday as the U.S. government ramped up pressure while tech companies, cryptocurrency exchanges and others worried about getting caught in the crossfire.
DarkSide, the Russian-speaking gang blamed by the FBI for a hacking attack that led to a six-day fuel pipeline shutdown, said it was going out of business after losing access to some of its servers.
Another major criminal gang said it would forbid encryption attacks on critical infrastructure, and forums where such gangs recruit partners said they were banning ads related to ransomware, analysts said.