WASHINGTON — For almost 20 years, since its inception, the post of US ambassador at large for international religious freedom at the State Department has been held by Christians. On Monday, however, Rabbi David Nathan Saperstein was nominated for the post by President Barack Obama, hours before the State Department prepared to deliver its annual report on religious freedom across the world.

“I am grateful that Rabbi Saperstein has chosen to dedicate his talent to serving the American people at this important time for our country,” Obama said when he announced the nomination. “I look forward to working with him in the months and years ahead.”

Rabbi David Nathan Saperstein leads the Religious Action Center of Reform Judaism and teaches First Amendment Church-State Law and Jewish Law at Georgetown University. He was a member of the President’s Advisory Council on Faith-Based and Neighborhood Partnerships from 2010 to 2011 and served on the US Commission on International Religious Freedom from 1999 to 2001.

The position of ambassador-at-large for international religious freedom was created in 1998 to lead the State Department’s Office of Religious Freedom, which is responsible for monitoring religious freedom abuses worldwide. The office presented its annual report on Monday.

Saperstein must pass a Senate confirmation before he can begin work. The position has been empty since October 2013 when Saperstein’s predecessor, Rev. Suzan Johnson Cook, resigned, citing financial strain.

Obama may have a personal soft spot for the Reform rabbi — it was Saperstein who delivered the invocation at the Democratic National Convention’s final session in 2008, before then-senator Barack Obama accepted the party’s nomination for president.

The Rabbinical Assembly’s Executive Vice President Rabbi Julie Schonfeld congratulated Saperstein, saying that “we are thrilled that the White House has recognized the extraordinary talent and dedication of our dear friend Rabbi David Saperstein of the Religious Action Center.

“Over the years, David has worked with the Rabbinical Assembly to advance a number of key projects related to American Jewish life, Israeli politics, global religious freedom, and more. We are proud of our work together, as well as of his many achievements with the Religious Action Center and we wish him mazel tov on this exciting nomination,” she continued in a statement. “We are confident that he will use this position to advance the important cause of religious freedom and that his work will be a great blessing both for him and for the State Department.”