WASHINGTON (CNN) – Calling Democratic health care bills "seriously deficient on the issues of abortion and conscience," the U.S. Conference of Catholic Bishops is urging priests around the country to speak out against the legislation from the pulpit this Sunday.

The conference - the leadership body of the Catholic Church in the United States - is distributing a flier to churches to insert in their weekly newsletters urging parishioners to contact their senators and representatives to ask them "to fix these bills with the pro-life amendments."

"The bills will have to change or the bishops have pledged to oppose them," the flier reads. "Our nation is at a crossroads."

Bishops are also planning to take out advertisements in diocesan newspapers with a similar message. "Americans would be forced to subsidize abortions through their taxes and health insurance premiums," the ad claims.

According to the language in the House health care bill unveiled Thursday, a government-run insurance option could cover abortions, but federal money would not pay for the procedure.

Abortion opponents dispute that and point to the non-partisan FactCheck.org, which wrote in late August that "private plans that cover abortion also could be purchased with the help of federal subsidies." Those subsidies, the site wrote, would be available to low and middle-income Americans who sign up for a public insurance option.

Abortion rights opponents in Congress, including Democratic Rep. Bart Stupak of Michigan, have been pushing leaders to add stronger language prohibiting the use of federal money to pay for abortions under new health care reforms.

UPDATE: A spokeswoman for Rep. Lois Capps, a Democrat who crafted the abortion funding language in the House bill, stressed that public funding cannot be used to fund abortions. She said qualifying low and middle-income Americans will be able to buy into an insurance exchange where they will have access to at least one plan that does cover abortions services and one that does not.

Capps' office said federal and private funds are kept separately in the exchange: abortion services could be paid for by private funds generated by patient premiums, and no one would receive a federal subsidy directly to do so.