Jeremy Hunt has promised to create a £6 billion fund to handle a no-deal Brexit if he becomes Prime Minister.
He said food producers should be treated like banks were during the 2008 financial crash.
“If you're a sheep farmer in Shropshire or a fisherman in Peterhead I have a simple message for you - I know you face uncertainty if we have to leave the EU without a deal,” he said.
“I will mitigate the impact of no-deal Brexit on you and step in to help smooth those short-term difficulties.”
He added: “If we could do it for the bankers in the financial crisis, we can do it for our fishermen, farmers and small businesses now.”
Under Mr Hunt’s plan a no deal budget would include a corporation tax cut to 12.5 per cent, and take 90 per cent of high street businesses out of rates.
“Britain deserves a leader who works tirelessly to get a deal but who is prepared to put the hard yards in preparing for no deal,” he said.
“You cannot leave the European Union on a wing and a prayer.”
Meanwhile, Theresa May has criticised leadership frontrunner Boris Johnson’s “do or die” approach to Brexit.
Mr Johnson told talkRADIO’s political editor Ross Kempsell he would leave the EU “do or die, come what may”.
Ms May said she expects her successor to deliver a deal with the EU.
“I still think we negotiated a good deal, I wasn't able to get a majority in Parliament for that deal,” she said.
“It will be up to my successor to get that majority, deliver on the vote and take us forward.”