A bill that would require religious groups to disclose their finances is up for debate today on Beacon Hill as the House of Representatives and the Boston Archdiocese and other religious groups advocating strongly against it.

The confrontational volleys between the church and bill supporters have increased as the date for the debate in the House draws closer.

Archbishop Sean P. O’Malley accused the sponsors of the bill of seeking to “violate religious freedom,” claiming that the legislation would allow the state to overrule financial decisions by the Catholic Church, according to a letter he sent out to every parish asking Catholics to fight against the bill.

Sen. Marian Walsh (Democrat-West Roxbury) said O’Malley was skewering the bill’s intent and told him, in a letter addressed to him yesterday, to cease his attempts to ”place fears in the hearts of the public.”

”This bill does not affect what any particular church believes or how they govern themselves,” Walsh said. ”That would clearly be a violation of the First Amendment.”

Lawmakers who support the measure say greater public scrutiny of religious institutions is needed, in part because of concerns raised during the clergy sexual abuse crisis and parish closings by the Boston Archdiocese.

Gov. Mitt Romney said, at a press conference Monday, he is considering vetoing the bill because he believes the bill would give the government too much regulatory control over churches and charities.

The bill would require all religious organizations that have annual revenues of more than $500,000 to file annual financial reports. It also would require them to provide a list of real estate holdings with the Attorney General’s office.

Romney said the bill seems to go further than the “routine regulatory interaction” and would be more invasive of the government than necessary, while also placing heavy burdens on religious organizations.

“I will not be able to support a bill which goes beyond a very routine regulatory interaction level but instead imposes the kind of onerous reporting requirements, oversight and intrusion in religious practice which is reportedly being considered by some associated with this bill.”

Romney’s opposition to the legislation surprised the bill’s advocates, who now must create enough support to override the possible veto.

Supporters of the bill believe Romney has the wrong impression of the measure.

“The governor misunderstands the bill,” Secretary of State William Galvin, a co-sponsor of the legislation, said in an interview with the Associated Press. “It is not intrusive as he thinks it is, and, in fact, it meets his criteria as he defined routine regulatory review. We can comply with that.”

Supporters are now asking for a meeting with the governor to discuss the measure.

Eric Fehrnstrom, the governor’s director of communication, said that Romney is open to meetings with proponents of the bill, but not until the legislation gets to his desk.