NASHVILLE (AP) - A group of evangelical pastors on Monday joined Roman Catholic clergy who oppose an Obama administration requirement that employees of religiously affiliated businesses receive birth control coverage.

Speaking at the National Religious Broadcasters convention in Nashville, Family Research Council President Tony Perkins said more than 2,500 pastors and evangelical leaders have signed a letter to President Obama asking him to reverse the mandate.

While most Protestants do not oppose contraception per se, the letter calls the mandate a violation of religious freedoms.

"This is not a Catholic issue," Perkins said. "We will not tolerate any denomination having their religious freedom impinged upon by the government."

The signers also object to a requirement that contraceptive coverage include the morning-after pill and other drugs and devices that prevent a fertilized egg from implanting in the uterus to grow.

The mandate does not apply to houses of worship, only religiously affiliated institutions like universities, hospitals and nonprofits.

After an uproar about the birth control rules earlier this year, Obama offered a compromise two weeks ago in which insurers, rather than religious groups, would pay for the contraceptive coverage.

Richard Land, president of the Southern Baptist Convention's Ethics and Religious Liberty Commission, promised to challenge the mandate both in court and in Congress.

"We are not going to stand by and allow our God-given rights, protected by the Constitution, to be atrophied, neutered, confined and restricted," he said.