WASHINGTON — The president of the U.S. Conference of Catholic Bishops is pressuring the House to act on immigration legislation before the end of the year, calling the issue “a matter of great moral urgency” that cannot wait.

Cardinal Timothy Dolan, the archbishop of New York, said in a letter to Speaker John Boehner, R-Ohio, on Thursday that he was troubled by reports that immigration reform is delayed in the House because lawmakers have a responsibility to resolve the issue.

Writing on behalf of the 450-plus U.S. cardinals and bishops, Dolan said they respectfully request that the House address the immigration issue as soon as possible.

The Senate passed a bill in June that would provide a path to citizenship for the estimated 11 million immigrants living here illegally and tighten border security, but the measure has stalled in the House, where Boehner and Republican leaders have argued for a piecemeal approach.

“As a moral matter … our nation cannot continue to receive the benefits of the work and contributions of undocumented immigrants without extending to them the protection of the law,” Dolan wrote. “Keeping these human beings as a permanent underclass of workers who are unable to assert their rights or enjoy the fruits of their labor is a stain on the soul of the nation.”

Dolan reiterated the bishops’ stand that immigration legislation includes a path to citizenship, reaffirms family reunification, deals with future flows of migrant workers and restores basic due process protections to immigrants.

He wrote Boehner, a Catholic, that immigration is “a challenge that has confounded our nation for years, with little action from our federally elected officials. It is a matter of great moral urgency that cannot wait any longer for action.”

Most House Republicans reject a comprehensive approach as well as the Senate bill, with many questioning the offer of citizenship to people who broke U.S. immigration laws to be in this country.