SAN FRANCISCO (AP) — The Roman Catholic archbishop of San Francisco is responding to a coalition of liberal politicians, fellow clergy and gay-rights leaders who are urging him to skip an upcoming March for Marriage event in Washington.

Archbishop Salvatore Cordileone chairs the U.S. Conference of Catholic Bishops’ subcommittee on the promotion and defense of marriage and is one of the scheduled speakers at Thursday’s march and rally.

House Minority Leader Nancy Pelosi is among the supporters of same-sex marriage who have asked Cordileone to cancel his appearance.

The archbishop says in a letter his office made public Monday that it’s his duty to uphold traditional views of marriage even if such views are unpopular.

He also challenged his critics to practice what they preach, writing that Americans who oppose same-sex unions have become targets of discrimination and intolerance.

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