The prime minister is to hold a special three-hour cabinet meeting to discuss preparations for a no-deal Brexit.
The government is also due to publish guidance on issues such as mobile phone roaming charges, driving licences and passports in the event of the EU and the UK not reaching an agreement.
The Brexit secretary has said the UK will not pay its financial settlement to the EU in a no-deal scenario.
He said the government was “stepping up” its contingency planning.
Theresa May’s proposals, set out after a Chequers summit in July, are fiercely opposed by some Tory MPs and the EU has also expressed reservations.
Image copyright Getty Images Image caption Roaming charges in EU countries were scrapped in 2017
Extra charges for people using their phones in another EU country were scrapped in June 2017. But the EU regulation banning them will not automatically be part of UK law after Brexit.
Mrs May has said the UK will no longer be part of the EU’s “digital single market” after Brexit.
In theory this means UK mobile operators, if they want to, could reintroduce the charges that could make it expensive to use a mobile phone in another EU country.
However, last month major operators told the BBC they had no plans to raise charges.
Mr Raab said the no-deal plans were “not something we want to have to implement”.
“No one should pretend that no deal would be straightforward,” he said.
“There would be risks and some short-term disruption. Extra checks at the EU border would bring delays for businesses.”
And trading with the EU on World Trade Organization terms – an outcome backed by a group of Brexiteers in a report this week – would be “inferior” to the current arrangements, he said.
But Mr Raab also criticised those he said were “scaremongering for political ends” about no deal being reached.
“It’s nonsense to claim that UK supermarkets would run out of food,” he said, adding that people should not be scared by the government’s request to pharmaceutical companies to stockpile extra medicine supplies.
More no-deal publications are expected in the coming weeks.