WASHINGTON — President Donald Trump plans to sign an executive order further weakening already-sparse enforcement of an IRS rule threatening the loss of tax-exempt status for religious organizations that endorse political candidates.

The order, which also affects nonprofits, promises “regulatory relief” for groups with religious objections to the preventive services requirement in the Affordable Care Act, according to a White House official. Those requirements include covering birth control and the move could apply to religious groups like the Little Sisters of the Poor, who have moral objections to paying for contraception.

Trump will sign the order as he marks the National Day of Prayer at the White House today. He was hosting members of his evangelical advisory board and planned to meet Roman Catholic leaders in the Oval Office before signing the order.

The White House did not release the full text of the order, and it was not clear just how the pledges stated within the order would be carried out. The order, which essentially would make it even less likely that a religious organization would lose its tax-exempt status because of a political endorsement, fall short of what religious conservatives expected from Trump, who won overwhelming support from evangelicals by promising to “protect Christianity” and religious freedom.

Ralph Reed, a longtime evangelical leader and founder of the Faith & Freedom Coalition, said he was “thrilled” by the language on the IRS restrictions on partisan political activity. “This administratively removes the threat of harassment,” Reed said in a phone interview. “That is a really big deal.” He said the language in the order related to the preventive care mandate will “ensure that as long as Donald Trump is president, that something like the Little Sisters of the Poor case will never happen again.”

Trump has long pledged to protect religious freedom. He promised to “totally destroy” the law prohibiting the political activities, known as the Johnson Amendment, when he spoke in February at the National Prayer Breakfast, a high-profile Washington event with faith leaders, politicians and dignitaries. Fully abolishing the regulation would take an act of Congress.