Lib Dem peer Lord Oakeshott, who led calls for Mr Diamond to resign in the wake of the scandal has said "Bob Diamond's departure is a great day for democracy".
He is the symbol of the gambling and greed we must root out of our banking system.
Now the top priority is to catch the criminals, break off the casinos from the basic banks and make them lend.
We must never again let the rich and powerful in the City or the media get their hands round the windpipe of Government.
Bob Diamond tonight angrily rejected suggestions that he misled MPs over regulators' concerns about activities at Barclays.
The Bank of England's Paul Tucker told MPs he refuted claims that he attempted to influence Barclays into manipulating the Libor rate.
MPs will be hoping the Deputy Governor of the Bank of England will shed some light on unanswered questions about rate-fixing at Barclays.