Donald Trump just fired the man who may have posed the greatest threat to his presidency.

His administration said the President fired James Comey, the FBI director, on Tuesday for his controversial handling of the inquiry into Hillary Clinton's email scandal.

But even if true, the claim rings hollow in the face of one salient fact: Mr Comey was burrowing deep into alleged connections between Mr Trump and Russia's Kremlin.

Not since Watergate has a president dismissed the person leading an investigation into themselves.

The decision sparked immediate comparisons with the "Saturday Night Massacre" of 1973, when the then president Richard Nixon dismissed Archibald Cox, the independent special prosecutor investigating Watergate.

Two of the justice department's top leaders resigned in protest rather than following Mr Nixon's directive to fire Mr Cox.