Obama 'embarrassed' for Iran letter signatories

US President Barack Obama said he was "embarrassed" for Republicans who signed a controversial letter warning Iran's leaders about reaching a nuclear deal with the White House. "I am embarrassed for them," Obama said in an interview with Vice media, which is expected to be released Monday. Forty-seven Senate Republicans -- including several potential 2016 presidential candidates -- signed the open letter to Iran's supreme leader published earlier this month. With a