Jeremy Hunt has said that if he becomes prime minister he will decide at the end of September whether to continue Brexit talks with Brussels or go for a no-deal withdrawal option.
The foreign secretary also said he would cancel August leave for Whitehall officials involved in Brexit preparations if necessary.
Mr Hunt said he would launch an all-out diplomatic effort to cut a new deal with the EU if he beats Boris Johnson in the race for the Tory leadership and Downing Street.
:: Watch Jeremy Hunt being questioned by Kay Burley in Battle For Number 10 – a special programme on Sky News at 7pm tonight
“It is important that the EU knows that we will do what it takes to make a success of a no-deal Brexit,” he said.
“We won’t blink as a country. That no-deal Brexit is not going to be an opportunity for them to successfully turn the screws on our country.
“I will start engaging with the EU straight away, throughout August.
“Then, when we have published our plan for a deal we think we can get through parliament by the end of August, we will start formal negotiations in September.”
He added: “There is a hard deadline in what I have said, by the end of September, I, as prime minister, will make a judgment as to whether there is a realistic prospect of a deal that can get through parliament in the short-term.
“And, if my judgement is that is not the case, talks will stop and we will put our heads down and focus on no-deal.”
Mr Hunt’s plans for a no-deal Brexit include a £6bn war chest for farmers and fishermen exporting to Europe.
During a speech in London he set out a 10-point plan, including a Cobra-style committee to “turbocharge” Whitehall preparations and keep Britain open for business in the event of World Trade Organisation (WTO) tariffs coming into effect.
“You cannot leave the European Union on a wing and a prayer,” he said. “Britain deserves better.
“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.
“I will mitigate the impact of no-deal Brexit on you and step in to help smooth those short-term difficulties.
“If we could do it for the bankers in the financial crisis, we can do it for our fishermen, farmers and small businesses now.”
Plans to keep goods flowing in and out of the UK, including emergency powers so ports and airports can coordinate nationally, will be led by a new national logistics committee led by the Department for Transport.
A no-deal Brexit budget should be prepared, including a corporation tax cut to 12.5%, increasing the annual allowance to £5m and taking 90% of high street businesses out of rates.
Mr Hunt added: “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 he would prefer the UK to leave the EU with a “new deal” that removes the Irish backstop and ensures a fully independent trade policy, which he will say is possible “if the Commission engages in good faith”.
Meanwhile, Mr Hunt’s leadership rival Mr Johnson will do away with public sector pay freezes, according to health secretary and ally Matt Hancock.
Mr Hunt made enemies in the NHS when he imposed new contracts on junior doctors in 2016 and oversaw the slowest period of investment in the NHS since its foundation.
Mr Johnson’s supporters have moved to capitalise on the weakness, with Mr Hancock telling The Times that public sector workers would get a “fair” pay rise under Mr Johnson.
Mr Hancock said: “Now that there’s money available we need to show the public sector some love – they do a brilliant job for the country,
“People in the public sector need to be properly rewarded for the brilliant job they do.
“Higher pay, not higher taxes, means a pay rise for everyone, including in the public sector.”
A two-year public sector pay freeze was introduced under David Cameron before rises were capped at 1% until 2017 under austerity measures.
Mr Hancock said he had just given junior doctors an 8% pay rise over several years and claimed this showed “the days of pay freezes are over”.
However, a spokesman for the Royal College of Nursing, which represents over 300,000 nursing staff in England, said warm words would not help pay the bills of workers whose pay still lagged behind levels a decade ago.
He added: “Until their pay matches the education and skills required, the government will struggle to fill the 40,000 vacant nurse jobs in England.”
Jeremy Hunt will tell MPs he is planning to ramp up preparations for a no-deal Brexit which will include a £6bn war chest for farmers and fishermen exporting to Europe. The Tory leadership candidate will set out a 10-point plan, including a Cobra-style committee to “turbocharge” Whitehall preparations and keep Britain open for business in the event of World Trade Organisation (WTO) tariffs coming into effect.