Mr Johnson was responding to a call from John Longworth, the head of the British Chambers of Commerce, to hold the in-out referendum next year in order to end uncertainty for businesses.
The Mayor of London told LBC Radio: “That’s not a bad idea by the way. Let’s get it done and knock it on the head and do it for the good of Europe. This problem is not going away. The whole Eurozone is mired in low growth, low productivity, they have a very anti-competitive environment there, a terrible system of regulation coming from Brussels.
“We have huge support in Britain for a Conservative-led campaign to reform the EU and get some change.”
Mr Johnson said that he believes voters in the UK “will vote to stay in a reformed Europe”.
“What we don’t want to see is an endless period of delay in which we don’t get the changes we need in Europe,” Mr Johnson said. “This is not just a narrow, British nationalistic tub-thumping point. We are campaigning for reform in Europe in the interests of everyone in the community. We have a lot of support from people around the table in Brussels.”
During a G20 finance ministers summit in Turkey, George Osborne, the Chancellor, hinted that the date could be brought forward, confirming that the Prime Minister would be "delighted" if he can complete renegotiation of the UK's EU membership earlier.