Trump-Russia collusion claims 'worse than Watergate', says former US intelligence official

The Watergate scandal that brought down a president "pales" in comparison with allegations that Donald Trump's election campaign colluded with Russians, a former US intelligence official has said.

James Clapper, director of national intelligence until Mr Trump took office in January, told Australia's National Press Club the cover-up of a 1972 burglary at the Democratic Party national headquarters in the Watergate complex in Washington that ended Richard Nixon's presidency "was a scary time".