Democratic presidential candidate Bernie Sanders on Friday declined an invitation to speak at AIPAC’s Policy Conference in Washington, D.C., next week, citing a scheduling conflict.

In a letter to Bob Cohen, AIPAC’s president, Sanders said his campaign schedule next week will prevent him from attending the largest pro-Israel annual gathering.

“I would very much have enjoyed speaking at the AIPAC conference,” Sanders wrote. “Obviously, issues impacting Israel and the Middle East are of the utmost importance to me, to our country and to the world. Unfortunately, I am going to be traveling throughout the West and the campaign schedule that we have prevents me from attending.”

“Since AIPAC has chosen not to permit candidates to address the conference remotely, the best that I can do is to send you a copy of the remarks that I would have given if I was able to attend,” he added.

Just in: Sanders letter to AIPAC explaining he can't make it bc he's campaigning. (The other candidates are going.) pic.twitter.com/T6s4KPRO1w

— Gabriel Debenedetti (@gdebenedetti) March 18, 2016

AIPAC had extended invitations to all of the current presidential candidates. “Our Policy Conference is also likely to be one of the few venues that these candidates will have to speak to a bipartisan audience between now and Election Day,” AIPAC said in a statement. “We are delighted for AIPAC to serve as the venue for presidential candidates to share their perspectives, and we look forward to welcoming them.”

Hillary Clinton is expected to address AIPAC during the Monday morning session, while Republican candidates Donald Trump, Ted Cruz and John Kasich will speak in the evening.

Sanders is the only candidate who expects his remarks to be distributed, or, somehow, be read aloud, to the 18,000 attendees.

"We should be able to get that speech to you Monday" reminds me of e-mails I would send to college professors about overdue papers.

— Nick Confessore (@nickconfessore) March 18, 2016

Following their speeches at AIPAC, Clinton, Trump, Cruz and Kasich are set to appear at CNN’s “Election Center” in Washington, D.C., for a 3-hour town hall with Anderson Cooper and Wolf Blitzer, while Sanders will be interviewed remotely from the campaign trail.