Security: U.S. and Saudi up the anti over Iran's alleged involvement in assassination plot

President Barack Obama and Saudi Arabia's King Abdullah have upped the anti over Iran's alleged involvement in a foiled plot to assassinate the Saudi ambassador in Washington.

Both are calling for a strong, international response.

With the arrest of one of two men said to have Iranian links, plus circumstantial evidence accrued by US security officials, Washington is convinced Tehran and part of the Revolutionary Guard masterminded the would be attack.