Dozens of synagogues and mosques across the United States and Canada are to take part in a first-of-its-kind three-day joint public relations campaign against anti-Semitism and anti-Muslim xenophobia beginning on Friday.

The initiative, which was given the code-name "Twinning," calls for close cooperation between rabbis and imams based in some of the largest cities in North America, including Boston, Atlanta, Chicago, Dallas, Denver, Detroit, Los Angeles, Minneapolis, New York, Palm Beach, St. Louis, and Washington DC.

Organizers say the venture, which will encompass an estimated 100,000 Jews and Muslims, will feature rabbis appearing before Muslim congregants in mosques while imams address Jewish worshipers at synagogues. In addition, workshops and symposiums will be held to examine ways to combat anti-Semitism and anti-Islamic hatred.

The event comes two weeks after Saudi King Abdullah appeared at an UN-sponsored interfaith conference in New York during which the monarch called for religious leaders to promote greater tolerance and moderation.

The event is the brainchild of Rabbi Marc Schneier of the Foundation for Ethnic Understanding, an organization devoted to improving ties between the Jewish and Muslim communities in the United States.

Schneier told Haaretz the venture was launched with the acknowledgement that the fight against extremism and radical Islam needs to be waged within Islam, thus requiring others to strengthen the moderate elements within Islam.