U.S. President Donald Trump was warned that attacking Iran could trigger retaliation against U.S.-Israeli air war, despite claims that Iran's retaliatory strikes against Qatar, Saudi Arabia, the United Arab Emirates, Bahrain and Kuwait were a surprise. The warning was confirmed by a US official and two sources familiar with U.K. intelligence reports. The claims have not been backed by U.N. intelligence reporting, which have been cited as reasons for the president's decision to join Israel in the air war against Iran. The White House did not immediately respond to a request for comment. The intelligence community had previously warned that Israel's plan to kill top Iranian leaders likely would result in retaliation against US military and diplomatic outposts.