WASHINGTON (KABC) — The Department of Homeland Security has discreetly revised the policy regarding how members of Congress can visit Immigration and Customs Enforcement facilities, leading to frustration among some lawmakers.

Although members of Congress have the legal right to conduct unannounced visits to ICE detention centers, the updated guidance on the department’s website now requires them to provide 72 hours’ notice via email before their visit. The agency claims this falls outside the jurisdiction of the detention center.

The policy further states that ICE “reserves the sole and unchallengeable right to decline a request or to cancel, reschedule, or terminate a tour or visit” if management deems it necessary to cancel.

“This unlawful policy is a smokescreen to deny member visits to ICE offices across the country, which are holding migrants – and sometimes even U.S. citizens – for days at a time,” said Democrat Bennie Thompson, the ranking member on the House Homeland Security Committee. “They are therefore detention facilities and are subject to oversight and inspection at any time. DHS pretending otherwise is simply their latest lie.”

The new policy comes as there have been encounters with lawmakers at ICE facilities, including outside of a detention center in New Jersey, which led to the arrest of a lawmaker.

ABC News contributed to this report.