The UK’s new Brexit secretary vowed to “intensify” talks in Brussels after his first meeting with EU chief negotiator Michel Barnier.
Mr Raab took over from David Davis, who resigned in protest at Theresa May’s post-Brexit trade plans.
He said it was “vital” make progress on the proposals in Mrs May’s White Paper.
The MP – who was a leading figure in the 2016 campaign to leave the EU – vowed to tackle talks with “renewed energy, vigour and vim”.
Mr Barnier said it was a “matter of urgency” to agree on a “backstop” plan to prevent a hard border in Northern Ireland if no deal is agreed – and said a “close partnership” on security was “more important than ever given the geopolitical context”.
Their meeting comes as the European Commission is instructing other EU states to prepare for a no-deal Brexit.
The commission paper warns that failure to reach a deal would have a considerable impact on European business and citizens.
Possible consequences, the paper says, include disruption to the aviation industry and goods from the UK being subject to custom checks.
Leo Varadkar has said his government is preparing for a no deal Brexit
Acting Cabinet Secretary Sir Mark Sedwill told MPs: “We wouldn’t want any of our European partners to think that we aren’t well prepared enough that it becomes a negotiating card on their side of the table.”
Speaking to MPs before setting off for Brussels, Mr Raab said he hoped Mr Barnier would “fully support” the proposals for post-Brexit trade with the EU in the government’s White Paper.
But he added the UK was stepping up preparations for a “no deal” Brexit and would shortly be publishing advice for businesses on how to cope with it to minimise “disruption”.
Labour’s shadow Brexit Secretary Sir Keir Starmer challenged Mr Raab to say whether he would “face down” Conservative MPs threatening to block a deal which does not meet their demands.
Mr Raab sidestepped the question and insisted his focus was on “narrowing the differences” and securing a “win-win deal” which was good for both the UK and European countries.
Mr Barnier was appointed to lead the European Union’s team of Brexit negotiators
Acting Cabinet Secretary Sir Mark Sedwill told a committee of MPs the civil service had “confidence” in its “no deal” planning.
“We wouldn’t want any of our European partners to think that we aren’t well prepared enough that it becomes a negotiating card on their side of the table,” he added.
Taoiseach (Irish prime minister) Leo Varadkar has said his government is also making contingency plans for “the unlikely event of a no-deal hard Brexit”.
Mr Varadkar said that – even if there is a deal – Ireland will need 1,000 new customs officers and veterinary inspectors to deal with changes in trade rules with the UK.
In the UK, the government has advised all its departments to have fully planned contingencies in place in the event of the UK withdrawing from the EU without an agreement.
However the government watchdog, the National Audit Office, has warned that, in the case of one department , there is “still much to do”.
On Thursday, Theresa May will be making her first visit to the Irish border since the Brexit referendum.
No 10 says the visit will “reaffirm her commitment to a Brexit that avoids a hard border and protects the Belfast Agreement”.