Ex-US diplomat: 'Last straw is not far off'

President Donald Trump asked FBI chief James Comey to drop an inquiry into links between his ex-national security adviser and Russia, US media report.

James Rubin, former assistant secretary of state, says the controversies surrounding Mr Trump are costing him political support.

"At some point, and nobody knows when, the damage will be so great, the straw will break the camel's back," he tells Radio 4's Today programme.