ORLANDO, Florida (JTA) – Birthright Israel co-founder Charles Bronfman called on the Reform movement to overtake Chabad as a provider of Birthright trips.

Speaking to a crowd of thousands Wednesday night at the biennial conference of the Union for Reform Judaism, Bronfman noted that 75 percent of participants on Birthright — which provides free 10-day trips to Israel for Jews aged 18-25 — identify as Reform, nondenominational or just Jewish.

Yet, Bronfman said, “Who is the largest trip provider? Chabad. And who performs the most conversions? Chabad. And who provides the largest number of post-trip programs? Chabad. It seems to me it should be you, not Chabad.”

Bronfman was at the Reform biennial in Orlando to receive the Eisendrath Bearer of Light Award for his establishment of Birthright and ongoing support for it. A philanthropist and businessman, Bronfman co-founded the program along with philanthropist and real estate magnate Michael Steinhardt a decade-and-a-half ago. To date, some 500,000 participants from 66 countries have gone on Birthright trips.

In his biennial speech, Bronfman also announced that Birthright is developing a mobile phone app to provide Birthright alumni with access to Jewish events in their city.

READ: 9 things to know about Reform Jews

Responding to the call to bolster Reform-led Birthright programming, Rabbi Rick Jacobs, the president of the Union for Reform Judaism, told Bronfman, “That’s a pretty audacious challenge you’ve put to us.”

Jacobs went on, “As you’ve said to us, rightfully, these are our young people. I’m going to tell you Charles, we’re going to meet that challenge and more. We’re never going to stop growing our numbers and increasing the impact of these transformational trips.”

Some 5,000 attendees are attending the Reform conference, which began Wednesday and runs through Sunday. The first day of the biennial coincided with the 20th anniversary of the assassination of Israeli Prime Minister Yitzhak Rabin, and at the opening plenary Rabbi Gilad Kariv, executive director of the Israel Movement for Reform and Progressive Judaism, led a remembrance of Rabin.

Vice President Joe Biden is due to speak at the conference on Saturday evening.