US President Donald Trump said Arab leaders need to take the lead in confronting extremism, and noted that they had suffered the deadliest toll of "fanatical violence" and that there was a humanitarian and security disaster that was spreading across the region.
The time has come for "honestly confronting the crisis of Islamist extremism," Trump said, calling on religious leaders to condemn extremist attacks.
Iran had nothing to do with the terror attacks on the US in September 2001, or subsequent attacks in Europe - including Germany, France and England - but he singled out Tehran in his speech.
"From Lebanon to Iraq to Yemen, Iran funds, arms and trains terrorists, militias and other extremist groups that spread destruction and chaos across the region," Trump said.
"Until the Iranian regime is willing to be a partner for peace, all nations of conscience must work together to isolate it."
Trump has openly espoused anti-Muslim sentiments. During a campaign speech in December 2015, he called for a "total shutdown" on Muslims entering the United States "until our country's representatives can figure out what the hell is going on."
His words shocked many Americans, with Trump's critics pointing out that the US Constitution prohibits religious discrimination.
"I think Islam hates us," Trump said during a CNN interview in March 2016. "There is a tremendous hatred there. We have to get to the bottom of it."
Despite his incendiary comments, or perhaps because of them, Trump is now extending a proverbial olive branch to Muslim leaders, saying Sunday that "this is not a battle between different faiths."
"This is a battle between barbaric criminals who seek to obliterate human life, and decent people, all in the name of religion," he said. "This is a battle between good and evil."
His speech came on the second day of his first trip abroad as president. It's a nine-day tour of the Middle East and Europe, with his next stop coming Monday in Israel.
Feted in Riyadh
And because of other tensions in the region (with Iran) and tensions with previous US President Barack Obama, Trump is being given a pass on his past remarks and is being feted by the Saudi monarchy.
The House of Saud chafed under pressure from the Obama administration to respect human rights. President Trump has made no such demands from a country well-known for its abysmal human rights record.
"We are not here to lecture - we are not here to tell other people how to live... or how to worship. Instead, we are here to offer partnership - based on shared interests and values," Trump said during his speech.
On Saturday the US and Saudi Arabia announced an arms deal worth nearly $110 billion (98 billion euros), which was described as the largest in US history. The US secretary of state, Rex Tillerson, said the military aid is aimed at countering "malign Iranian influence."
Nearly three dozen heads of state and governments from Muslim-majority countries are in the Saudi capital for the Arab Islamic American Summit. They represent primarily Sunni states friendly to Saudi Arabia.
Much of the summit's focus is on countering the perceived threat posed by the Shiite-led Iranian government. Tehran and Riyadh are at odds on a range of regional conflicts, including the civil wars in Syria and Yemen.
bik/cl (AFP, AP, Reuters, dpa)