Contrary to his promise not to criticize the U.S. president on foreign soil, Republican presidential hopeful Mitt Romney slammed his Democratic rival during his speech in Jerusalem on Sunday, saying public expressions of diplomatic distance is damaging to Israel.

"Diplomatic distance that is public and critical emboldens Israel's adversaries," said Romney, alluding to the Obama administration's stance on Israel.

Romney's speech followed a day spent meeting Israel's leaders on his official visit to the country. Joining the crowd was billionaire Sheldon Adelson, who has donated millions of dollars to Romney's campaign, and those of other Republicans.

Romney opened his speech by saying it was a "moving experience to be in Jerusalem," which he described as, "Israel's capital."

He went on to mention the U.S.-Israeli relationship, saying, "We serve the same cause and we have the same enemies. The security of Israel is a national security interest of the United States."

"An enduring alliance is more than strategic; it's a force for good in the world," he said, adding that the U.S. and Israel are part of the same "fellowship of democracies," and that the two countries "speak the same language" of freedom and justice.

Romney was met with strong applause when he mentioned the Munich Massacre of 1972, in which 11 Israeli Olympic athletes were slain. "Tragedies like this are not reserved to the past" he said, adding that they are a constant reminder of hate, and the will behind "acts of hate." His comments came amid controversy over the International Olympic Committee's refusal to commemorate the massacre with a moment of silence during the London 2012 opening ceremony.

After his meeting with Prime Minister Benjamin Netanyahu earlier in the day, in which the two stressed the dangers of a nuclear Iran, Romney described the Islamic Republic in his speech as "the most destabilizing nation in the world," and added that Tehran supports terrorists and the Assad regime. He added that Iranian leaders speak of wiping Israel off the map, and that anyone who does not believe their rhetoric is naive or worse.

"The ayatollahs in Iran are testing our moral defenses," Romney told the crowd gathered in Jerusalem that, adding that the conduct of Iran's leaders "gives us no reason to trust them with nuclear material."

"We should employ any and all measures" to prevent Iran from following a nuclear course, he said, adding, "We recognize Israel's right to defend itself and America's right to stand with you."

The Republican hopeful also stressed that it was the responsibility of the international community to ensure that Egypt uphold the peace agreement with Israel.

Romney also took the opportunity to express his admiration of Israel. "You have embraced economic liberty... You support technology, not tyranny nor terrorism," he said. 

Earlier on Sunday, Romney met with President Shimon Peres, who emphasized that he is sure that the policies of the Obama administration in regards to the Iranian issue are the right ones.

Romney also met with opposition leader Shaul Mofaz. His meeting with Labor Party head Shelly Yacimovich was cancelled at the last minute.