An agreement approved Monday between U.S. officials and environmentalists would temporarily ban the use of predator-killing cyanide traps on Colorado public lands.

Federal workers already had stopped using the devices except on the state's private lands, a government spokeswoman said.

Public pressure for a nationwide ban on the traps — meant to protect livestock from predators — has increased since an Idaho teenager was injured and his dog killed by one in March.

The environmental groups WildEarth Guardians and the Center for Biological Diversity sued the government earlier this year alleging cyanide traps kill wildlife and pets indiscriminately.

Under Monday's agreement, which was approved by U.S. District Judge Wiley Daniel, the Agriculture Department must re-consider the environmental impacts of the traps as part of its predator management program in Colorado.

Agriculture Department spokeswoman Tanya Espinosa said the devices haven't been used for years on federal or state lands in Colorado, despite an agency study from January that suggested they were allowed on state land. Espinosa said the inclusion of state lands in that study was unintended.

Stuart Wilcox with WildEarth Guardians said he was skeptical of the claim the traps aren't currently being used on public lands in Colorado.

"The record-keeping and accountability for that agency is pretty shoddy," Wilcox said. "Whether it's through negligence or intentional use, I would be very surprised if it's not happening."

Under the terms of the deal disclosed Monday, the agency's Wildlife Services division plans to complete the study of its Colorado predator removal program by Aug. 1, 2018.

The government in June launched a nationwide review of the devices also known as M-44s or "cyanide bombs." The traps are partially buried and baited to attract predators, and animals that trigger them are sprayed with a deadly dose of cyanide.

Espinosa declined to say when the review might be done. An agreement is pending in a separate lawsuit challenging the devices' use nationwide.

Currently authorized for use in 15 states, M-44s last year killed more than 12,500 coyotes and 852 other animals including raccoons, opossums and skunks, Espinosa said. More than 16,500 traps were deployed nationwide, she said.

The government's January study said federal workers used 122 M-44s in Colorado between 2010 and 2014. The study did not specify where the traps were set.