More than 50 African American church leaders from Ohio have called out U.S. Sen. Rob Portman (R-Ohio) for supporting an amendment attempting to block the creation of new National Park units through the Antiquities Act.

President Barack Obama just used the act for the 22nd time during his administration, last week creating the Sand to Snow National Monument, Mojave Trails National Monument, and Castle Mountains National Monument – a total of 1.8 million acres of protected public lands in California.

The U.S. Senate struck down an attempt by Sen. Mike Lee (R-Utah) to limit a president’s ability to name new national monuments without the consent, within three years, of Congress and the state in which the proposed monument was located. Portman voted in favor of Lee’s amendment to an energy bill, but it failed by a 47-48 vote, with four Republicans joining Democrats in opposition.

“Our responsibility to care for Creation is coupled with our duty to preserve and honor the story of all Americans, and ensure all our children have equitable access to healthy recreation and the opportunity to find their own story in our park system,” the black church leaders wrote. “As leaders in the black church community in Ohio, we call on you to support the Antiquities Act and oppose legislation or amendments that would undermine its use or blanket it in red tape.”

Paid advertising highlighting the black church community’s dismay over Sen. Portman’s action was scheduled to begin running in Ohio media outlets on Thursday.

Click here for the full letter.

Portman has drawn the ire of the Ohio black clergy and other conservation groups because he previously was perceived as a supporter of the parks, which in 2016 are celebrating the centennial of the National Park Service. He in fact received the Bruce F. Vento Public Service Award from the National Park Trust just last summer (see video below) and sits on the Senate subcommittee on national parks. The senator supported full funding in 2016 of the Land and Water Conservation Fund, the use of the LWCF to purchase inholdings at Cuyahoga Valley National Park in Ohio, and sponsored legislation supporting the creation of the Charles Young Buffalo Soldiers National Monument in Xenia, Ohio.

The Antiquities Act was the first law to establish that public lands are critical to American heritage. It obligates federal agencies that manage the public lands to preserve for present and future generations the historic, scientific, commemorative, and cultural values of the archaeological and historic sites and structures on these lands. It also authorizes the President to protect landmarks, structures, and objects of historic or scientific interest by designating them as National Monuments.

Nearly half of national parks, including iconic units such as Statue of Liberty and the Grand Canyon – originally were protected by the Antiquities Act.

Last week, the League of Conservation Voters (LCV) launched a $20,000 Facebook campaign critical of Portman and Sen. Joe Manchin (D-W.Va.) for supporting the Lee amendment.

“Politicians who vote to gut the law first used to protect half our national parks are not pro-parks,” Gene Karpinski, president of the LCV, said in announcing the campaign. “As we celebrate the National Park Service’s Centennial year, it is incomprehensible that these senators support tearing down the very law that ensured we could quickly protect our country’s special places for future generations. When they vote to undermine proven and successful conservation laws, it’s communities across the country that suffer when they are denied the economic benefits of preserving their natural and cultural heritage.”