The international community expressed outrage on Tuesday over US presidential candidate Donald Trump's called for a "total and complete shutdown of Muslims entering the United States. Amid fear of terrorism, the Republican candidates for president for months have escalated their rhetoric about the place of Muslims in the United States. A Muslim shouldn't be president. Muslims fleeing war-torn Syria and Iraq should be barred from the country. Mosques should be placed under surveillance and shut down if people are radicalized in them. Republican front-runner Donald Trump's call Monday for a "total and complete shutdown of Muslims entering the United States" was the latest salvo for a party aggressively testing the boundaries between concerns about security and discrimination against a religious group. For most of Trump's rivals in the 2016 race, as well as numerous other Republicans, it was also the proposal that finally crossed that line. "Donald Trump is unhinged," former Florida Gov. Jeb Bush said via Twitter. "His ‘policy' proposals are not serious." The British government condemned comments by Trump as "wrong." British Prime Minister David Cameron "completely disagrees" with the remarks, which are "divisive, unhelpful and quite simply wrong," a spokeswoman for the Conservative leader said. Campaign rhetoric in the United States is harming a vital US resettlement program for Syrian and other refugees fleeing war and persecution, the United Nations refugee agency said on Tuesday. UNHCR spokeswoman Melissa Fleming, asked about Trump's remarks, told a news briefing in Geneva: "What (Trump) was speaking of was an entire population but this also impacts the refugee program. Because our refugee program is religion-blind. Our resettlement program selects the people who are the most in need." Bassem Youssef, former talk show host known as the Jon Stewart of the Middle East, wrote on Twitter: "I didn't know Donald Trump was fluent in Nazi." Yara Faris, a 23-year-old journalist in the West Bank, who hopes to study international journalism at Columbia University, said: "The US will always be the best place to study, and I don't think the US would deny Muslims entry just because they are Muslims." "I see Trump as a crazy man. He always gives crazy statements and recently I read a report that shows that 60 percent of Trump's statements were based on wrong information." Usama Sallah, prominent Palestinian businessman in Al-Quds who lived in the US for 14 years, said: "I think that these statements are a shame. This is not the United States that I knew, and I'm sure that the majority of the Americans don't agree with it because it doesn't represent American values." "I will continue to visit the United States whenever possible because I know that America is a great country in which there is no place for such racist opinions. And for those who agree with him, I ask: How would you feel if Arab and Muslim countries decided to ban Americans from entering them?" Sam Bahour, a Palestinian-American business consultant who moved from Youngstown, Ohio, to Ramallah, West Bank, in the 1990s, called the comments "disgraceful" and "absurd." "The backlash is going to be against Muslims. The Muslim community understands the inherent racism in some pockets of US political life." "This makes the melting pot not melt at the end of the day." Bahour said relatives in the US have been telling him "how they are hearing comments in the street, supermarkets, really racist comments. It's not going to be the same being a Muslim in America, even once this passes." Aziza Yousef, a computer science professor at King Saud University in Riyadh, said: "He's racist... I think Trump is representing himself. I don't think he represents Americans." "Why is it that when there are crazy people who happen to be Muslim, they blame all Muslims? I will not be responsible for someone who commits a crime who happens to be a Muslim. I will not defend myself or defend Islam because a guy or person who happens to be Muslim did something stupid." Yousef is traveling to her vacation home in Virginia this weekend with her children and grandchildren as she does every year. "I spend a lot of money there three to four months out of the year. Muslim tourists and those that live there as students help the economy of the United States."