London, Aug 18 (IANS): British Prime Minister Boris Johnson will tell European Union (EU) leaders that there needs to be a new Brexit deal when he makes his first trip abroad as the Prime Minister later this week.

The UK will leave the European Union (EU) on October 31 with or without a deal, Johnson will insist.

Meanwhile, the Sunday Times has printed leaked government documents warning of food, medicine and fuel shortages in a no-deal scenario, the BBC reported.

A source told the BBC that a former minister leaked the dossier to try to influence discussions with EU leaders.

The documents say the cross-government paper on preparations for a no-deal Brexit, code-named Operation Yellowhammer, reveals that the UK could face months of disruption at its ports.

It also states that plans to avoid a hard border between Northern Ireland and the Republic of Ireland are unlikely to prove sustainable.

According to the dossier, reported by the Sunday Times, leaving the EU without a deal could lead to the following situations:

* Fresh food becoming less available and prices rising.

* A hard Irish border after plans to avoid checks fail, sparking protests.

* Fuel becoming less available and 2,000 jobs being lost if the government sets petrol import tariffs to 0 per cent, potentially causing two oil refineries to close.

* UK patients having to wait longer for medicines, including insulin and flu vaccines.

* A rise in public disorder and community tensions resulting from a shortage of food and drugs.

* Passengers being delayed at EU airports, Eurotunnel and Dover.

* Freight disruption at ports lasting up to three months, caused by customs checks, before traffic flow improves to 50-70 per cent of the current rate.

The Downing Street source told the BBC the leaked document "is from when ministers were blocking what needed to be done to get ready to leave and the funds were not available".

Michael Gove, who is responsible for overseeing the devolution consequences of Brexit, said in a tweet that Operation Yellowhammer was "a worst case scenario".

"V significant steps have been taken in the last 3 weeks to accelerate Brexit planning," he added.

Energy Minister Kwasi Kwarteng told Sky News' Sophy Ridge on Sunday: "I think there's a lot of scaremongering around and a lot of people are playing into project fear," he said.

But a former head of the British civil service, Lord Bob Kerslake, who described the document as "credible", said the dossier "lays bare the scale of the risks we are facing with no-deal Brexit in almost every area".

"These risks are completely insane for this country to be taking and we have to explore every avenue to avoid them," he told BBC Radio 4's Broadcasting House.

Irish Deputy Prime Minister Simon Coveney said, in a tweet, that Ireland had "always been clear" a hard border in Ireland "must be avoided".

The Irish backstop -- the provision in former British Prime Minister Theresa May's withdrawal agreement that could see Northern Ireland continue to follow some of the same trade rules as the Republic of Ireland and the rest of the EU, thus preventing a hard border -- was an "insurance policy" designed to protect the peace process, he said.

The leak comes as Johnson prepares to travel to Berlin to meet German Chancellor Angela Merkel on Wednesday, before going to Paris to meet French President Emmanuel Macron on Thursday.

Johnson is expected to say Parliament cannot and will not change the outcome of the 2016 referendum and insist there must be a new deal to replace May's withdrawal agreement -- defeated three times by the MPs -- if the UK is to leave the EU with a deal.