The U.S. ambassador to the United Nations on Wednesday took aim at nations she said are failing to help refugees fleeing war in the Middle East and elsewhere, calling anti-immigrant rhetoric and sentiment misguided. Millions of Syrians have found refuge in bordering countries such as Turkey and Lebanon, but other wealthier nations have provided shelter to far fewer people seeking new lives, Samantha Power said in a speech at the United States Institute for Peace in Washington.

More than 60 million people fled their homes last year, and nearly 5 million Syrians have fled their country since the outbreak of civil war in 2011, according to the U.N. High Commissioner for Refugees (UNHCR). Yet at the end of last year, just 10 countries were hosting some 45 percent of the world's refugees, Power said. "Even as the crisis continues to grow, many countries are making no effort at all to do their fair share," Power said. "Worse, some countries are actually cutting back on the number of admitted refugees, or they've said that they won't take any refugees at all," she said. Germany has pledged to take in hundreds of thousands of refugees, and Canada has admitted nearly 30,000 Syrian refugees since late last year. The United States has promised to take in 10,000 Syrian refugees but has let just 4,500 in since 2013, according to U.S. figures cited by UNHCR. Power said calls to halt refugee programs over security concerns after deadly attacks in Paris last year and in Orlando, Florida this month were "misguided."

"What is not appropriate ... (is) failing to see the difference between a homegrown terrorist and a refugee, or drawing misguided and discriminatory conclusions about entire groups of people based on the countries from which their families immigrated or the faith that they observe," she said. Her speech came as support for politicians with anti-immigration messages has grown in such rich countries as Great Britain, which has just voted to leave the European Union. The United States is hosting a summit on refugee and migrants in September, when it will ask other countries to step up and take in more refugees, Power said.