BBC AMERICA: US President Barack Obama has criticised a letter from Republican senators to Iran, accusing them of "interfering" in ongoing nuclear talks.
He said the 47 senators made an "unusual coalition" with Iran's hard-line religious leaders.
The letter reminds Iran that any deal is just an executive agreement unless it gets congressional approval.
Talks on Iran's nuclear programme are at a critical stage, with an outline agreement due on 31 March. (+ BBC video) » | Monday, March 09, 2015