The presidents of China, Russia, Iran and the United States are scheduled to speak at the 70th annual U.N. General Assembly of world leaders in September — a rare appearance for Russian President Vladimir Putin and the first for Chinese President Xi Jinping.

The United Nations issued its first draft list of speakers Monday for what could be its largest ever gathering of world leaders.

Pope Francis is also set to address the General Assembly a few days before President Barack Obama, Putin, Xi and Iranian President Hassan Rouhani speak at the gathering.

The list of speakers is expected to change several times before the high-level ministerial meeting begins Sept. 28, but so far countries not sending a head of state include India, Britain, Syria, Saudi Arabia and North Korea.