Not everybody was so happy though, with former Conservative deputy prime minister, Lord Heseltine, calling Mr Johnson’s decision “illogical”.
He said: “If it takes you this long to make up your mind about something so fundamental and you still have questions, then surely the right option is to stay with what you know rather than risk our economy and security with a leap in the dark.
“If he were to be successful in his ambition to cut us off from Europe, the flags would fly in Frankfurt and Paris in his honour.
“At a stroke, he would have blown away the safeguards for our financial services industry that the Prime Minister has just secured.
“That is to risk countless jobs across our country from Edinburgh in the north to Bournemouth in the south and, of course, London itself.”
Dozens of FTSE-100 chiefs are to publish a letter on Tuesday warning if Britain left the EU it would spell disaster for the UK’s economy.