Riyadh — The Arab Islamic American Summit taking place at a crucial time is a key event in countering extremism and combating terror, said Custodian of the Two Holy Mosques King Salman welcoming US President Donald Trump and 55 leaders of Arab and Muslim countries here on Sunday. The King emphasized cooperation in fighting terrorism in all of its forms and manifestations. "We affirm taking serious steps to further strengthen partnership with the US. Our responsibility toward the global community is to stand united in the fight between good and evil. We have succeeded in countering most terror acts," the King said. "The Iranian regime has been at the head of the global terror since the period of Khomeini. We have regard for the Iranian people who should not be blamed for the crimes of their regime," King Salman said. "We did not know terrorism and extremism until the Khomeini revolution reared its head," the King said. "Our responsibility before God and our people and the whole world is to stand united to fight the forces of evil and extremism wherever they are ... The Iranian regime represents is the spearhead of global terrorism." [caption id="attachment_146842" align="aligncenter" width="700"] Custodian of the Two Holy Mosques King Salman, US President Donald Trump, Arab and Muslim leaders pose for a photo during Arab Islamic American Summit in Riyadh on Sunday. — Reuters[/caption] The King also said in his speech that Saudi Arabia would not be lenient in trying anyone who finances terrorism. "We will never be lenient in trying anyone who finances terrorism, in any way or means, to the full force of the law." Saudi Arabia was also determined to "eliminate the Daesh group," the King said. King Salman announced the launch of the Center of Moderation to Counter Extremism and Combat terror. The Arab Islamic American Summit started at King Abdulaziz International Convention in Riyadh. King Salman on Sunday tweeted that the Summit would cement a global anti-terror alliance. "I welcome my brethren and friends to the Arab Islamic American Summit, which will bring positive horizons for our region and the world. We will cement our alliance against extremism and terrorism," the King tweeted following a meeting between Trump and Gulf leaders, which aimed at addressing security and defense issues. The ‘Riyadh Declaration' adopted at the end of the Arab Islamic American Summit is based on four pivotal points. They are: 1. Strengthening joint work to combat extremism and terrorism. 2. Fostering values tolerance among peoples and religions in a way that serves all of humanity. 3. Protecting waterways and sea passages and fighting piracy. 4. Condemnation of all calls for sectarianism and prevention of Iranian intervention and practices in the region.