French President Francois Hollande (right) and Iraqi President Fuad Masum attend the Conference for Peace and Security in Iraq at the Ministry of Foreign Affairs in Paris on Monday. The two leaders were among those urging quick action against Islamic State militants. David Silpa/UPI/Landov hide caption

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British Prime Minister David Cameron told the House of Commons on Monday that he wants to give police the power to seize the passports of Islamist fighters bound for Iraq and Syria. PA Photos /Landov hide caption

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Britain's Prime Minister David Cameron speaks at a news conference in London on Friday after the U.K. raised its terror alert level. Paul Hackett/PA Photos/Landov hide caption

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On the sidelines of the EU summit in Brussels, U.K. Prime Minister David Cameron said the choice of Jean-Claude Juncker to head the European Commission marks "a bad day for Europe." John Thys/AFP/Getty Images hide caption

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President Obama and British Prime Minister David Cameron in the Oval Office of the White House on Monday. Jim Watson /AFP/Getty Images hide caption

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