BALTIMORE — The nation's Roman Catholic bishops vowed Tuesday to forcefully confront the Obama administration over its support for abortion rights, saying the church and religious freedom could be under attack in the new presidential administration.

In an impassioned discussion on Catholics in public life, several bishops said they would accept no compromise on abortion policy. Many condemned Catholics who had argued it was morally acceptable to back President-elect Barack Obama because he pledged to reduce abortion rates.

And several prelates promised to call out Catholic policymakers on their failures to follow church teaching. Bishop Joseph Martino of Scranton, Pa., singled out Vice President-elect Joe Biden, a Catholic and Scranton native, who supports abortion rights.

"I cannot have a vice president-elect coming to Scranton to say he's learned his values there when those values are utterly against the teachings of the Catholic Church," Martino said. The Obama-Biden press office did not immediately respond to a request for comment.

Archbishop Joseph Naumann of the Diocese of Kansas City said politicians "can't check your principles at the door of the legislature."

Naumann has said repeatedly that Kansas Gov. Kathleen Sebelius, a Catholic Democrat who supports abortion rights, should stop taking Holy Communion until she changes her stance.

"They cannot call themselves Catholic when they violate such a core belief as the dignity of the unborn," Naumann said Tuesday.

The discussion occurred on the same day the bishops approved a new "Blessing of a Child in the Womb." The prayer seeks a healthy pregnancy for the mother and makes a plea that "our civic rulers" perform their duties "while respecting the gift of human life."

Chicago Cardinal Francis George, president of the U.S. Conference of Catholic Bishops, is preparing a statement during the bishops' fall meeting that will press Obama on abortion.

The bishops suggested that the final document include the message that "aggressively pro-abortion policies" would be viewed "as an attack on the church."

Along with their theological opposition to the procedure, church leaders say they worry that any expansion in abortion rights could require Catholic hospitals to perform abortions or lose federal funding. Auxiliary Bishop Thomas Paprocki of Chicago said the hospitals would close rather than comply.

During the campaign, many prelates had spoken out on abortion more boldly than they had in 2004, telling Catholic politicians and voters that the issue should be the most important consideration in setting policy and deciding which candidate to back.

Yet, according to exit polls, 54 percent of Catholics chose Obama, who is Protestant. The new bishops' statement is meant to drive home the point in a way that cannot be misconstrued.