WASHINGTON, June 10 (Reuters) - U.S. President Donald Trump on Wednesday said Tehran has taken too long to negotiate a deal and would now "have to pay the price" after Iran and the United States exchanged strikes in the region amid reported efforts to continue talks. WASHINGTON, June 10 (Reuters) - U.S. President Donald Trump on Wednesday said Tehran has taken too long to negotiate a deal and would now "have to pay the price" after Iran and the United States exchanged strikes in the region amid reported effort... [1254 chars]