Iran is reopening the gates to delegations from the US religious community as part of a broader outreach meant to smooth the way for a nuclear agreement and improve relations with the United States.

Since March, three major faith-related US delegations have visited the Islamic Republic of Iran for meetings with senior Shiite Muslim theologians and government officials.

A Roman Catholic group, led by Bishop Richard Pates of Des Moines, Iowa, drafted a joint declaration against the “production, stockpiling, use and threat to use weapons of mass destruction” that was signed by Pates, Cardinal Theodore McCarrick — the retired archbishop of Washington — and two Iranians, including Ayatollah Ali-Reza A’arafi, a senior member of the Supreme Council of the Society of Qom Seminary Scholars.

In Iran for six days in March, the six-member US group also met Ayatollah Morteza Moghtadaei, a member of the Assembly of Experts, which chooses Iran’s supreme leader, and had dinner with Ayatollah Javad Shahristani, Iraqi Grand Ayatollah Ali Sistani’s representative in Qom. Returning to the United States, they briefed US officials including White House chief of staff Denis McDonough, Deputy Secretary of State Bill Burns and Sen. Tim Kaine, D-Va., said Stephen Colecchi, director of the Office of International Justice and Peace at the United States Conference of Catholic Bishops, which organized the trip. He said they are also sharing their experiences with bishops and congregations all around the United States.