Cabinet Minister Michael Gove has admitted the Government cannot guarantee "frictionless" trade with the EU post-Brexit.
His comments came just hours before the UK was due to leave the EU at 11pm on Friday, beginning a 12-month transition period during which the PM hopes to conclude a free trade agreement with the bloc.
EU leaders have repeatedly warned that the UK must adhere to EU standards in order secure a sought after free-trade agreement. However, Boris Johnson will declare in a speech next week that "sovereignty is more important than frictionless trade".
Less convergence between UK and EU standards, however, will increase the likelihood of checks on goods entering Northern Ireland from Great Britain.
Speaking to BBC Breakfast, Mr Gove - a prominent figure in the 2016 leave campaign - was asked if he could guarantee frictionless trade after Brexit.
He replied: ‘No. We want trade to be as frictionless as possible but the EU is clear, you can only have fully frictionless trade if you accept all of their rules, if you accept all their laws, you are subordinate to their judges, you are subordinate to their political structures.
"We voted to be independent. Now, we want to have as close as possible relationship with the EU and the approach that we want to take is built on the relationship that they have with Canada.
"That means that we want to have a relationship where there are ultimately no tariffs, no quotas on our trade but there will be some regulations that will differ in Britain, we will do things in a way which is better for our economy.
"That may mean that when it comes to trading with Europe there are some bureaucratic processes there that aren’t there now," he said.
Less than 10 days ago, Boris Johnson stood up in the Commons and "emphatically" promised "unfettered access" for goods moving between Northern Ireland and Great Britain, following requests of assurances by the DUP.
Stephen Kelly of Manufacturing NI questioned such a promise, stating the entire business and political community in Northern Ireland "remains puzzled" by the suggestion that the UK can "deliver what is clearly undeliverable at this point".
“Both [Boris Johnson] and his Chancellor of the Exchequer have said there will not be any alignment, any customs agreement or any single market participation from the UK in a new trade deal, so there are direct contradictions between the stated position of government policy and the Prime Minister’s words,” he said.
The now-ratified Brexit withdrawal agreement stipulates that Northern Ireland will remain in the UK customs union, but will be subject to EU customs rules.
In order to avoid a hard border between Northern Ireland and the Republic, Northern Ireland will have to retain regulatory alignment with the EU - creating a de facto trade border down the Irish Sea.
Michael Gove said the Government will do "everything possible" to minimise friction in the interests of the UK economy.
"Critically, as we leave the EU we will be able to set the rules in the interests of the British economy and that means that we will see all sorts of procedures, all sorts of bureaucracy that in the past have held British business back, that can go," he added.