"I'm telling you that if we vote on June 23 and take back control of our country, our economy and our democracy then we can prosper and thrive and flourish as never before," Johnson addressed Vote Leave supporters, as quoted by the British television and press.
Describing the Vote Leave and Vote Remain camps as a battle between "the little platoons against the big battalions, David and Goliath," Johnson appealed to the undecided to "vote for democracy against bureaucracy."
"We know what happened to Goliath… We are better, braver, stronger and greater than those on the remain side are currently saying that we are," the former mayor argued.
Saturday marks the biggest day of cross-party canvassing since the Brexit campaign officially kicked off in early April.