WASHINGTON (AP) -- WASHINGTON (AP) - American bishops are urging Roman Catholics to join a campaign to defend religious liberty and resist laws that the church considers unjust.

The bishops issued the call Thursday in a new document on religious freedom. They say they're responding to recent clashes between faith groups and the government on issues ranging from contraception to adoption to aiding illegal immigrants.

The highest-profile disagreement has been over the Obama administration's new mandate that most employers cover birth control costs for workers.

The administration has offered a compromise for church-affiliated groups, but bishops say the changes don't go far enough.

The bishops say their efforts are nonpartisan. They plan a national "Fortnight of Freedom" devoted to prayer and study focused on religious freedom from June 21 to July 4.