The UK will not pursue any post-Brexit relationship with the EU "that relies on alignment with EU laws", Prime Minister Rishi Sunak has said.
It follows reports that some in government want to move towards a Swiss-style deal, with less trading friction and more migration.
Switzerland can trade easily with the bloc, but must follow some EU rules.
Mr Sunak told business leaders that control of migration was one of the immediate benefits of Brexit.
Speaking at the CBI conference in Birmingham he said: "I voted for Brexit, I believe in Brexit.
"I know that Brexit can deliver, and is already delivering, enormous benefits and opportunities for the country."
He argued that the UK was now able to "have proper control of our borders".
He also said the UK was free to pursue trade deals with "the world's fastest-growing economies".
Over the weekend, The Sunday Times reported that senior government figures were considering pursuing a Swiss-style deal.
Government ministers as well as Downing Street have denied the story, but it still prompted concern from some Brexit-supporting Conservatives.
Former minister Simon Clarke tweeted: "I very much hope and believe this isn't something under consideration. We settled the question of leaving the European Union, definitively, in 2019."
And Lord David Frost, who negotiated the existing deal, said: "I hope the government thinks better of these plans, fast."
Switzerland is not a member of the EU, but does have a several agreements with the trading bloc, and has access to the single market for most of its industries. It also pays into the EU budget and has freedom of movement, meaning EU citizens can live and work in the country.
Last week, Chancellor Jeremy Hunt said he hoped the UK would be able to remove trade barriers with the EU but added that it would "take time".
"Having unfettered trade with our neighbours and countries all over the world is very beneficial to growth," he said.
He was speaking after delivering his Autumn Statement in which he confirmed the UK was in recession and that the economy was due to shrink further.
The chancellor's statement was accompanied by an economic forecast from the Office for Budget Responsibility which said Brexit had had a "significant adverse impact" on UK trade.
Does Rishi Sunak really want to reopen the Brexit Pandora's box?
Not if you listen to ministers on the airwaves, spokespeople in Downing Street and the PM himself this morning.
You can understand why. The Conservative Party has been a pretty fractious place in the last few months. Revisiting the Brexit question would throw all the debates from 2016 onwards back into the open.
Labour's leadership don't want to spend months talking about it either.
But even if the PM isn't going to revisit a Swiss-style arrangement, the debates about post-Brexit Britain aren't going away.
There are questions over migration, Northern Ireland and broader trade with Europe. Reducing friction is only likely if there are other compromises with Brussels.
So even if the fundamentals aren't back on the table, parts of the debate over Brexit are.
Asked if Brexit had damaged UK trade, Home Office Minister Robert Jenrick told the BBC it was hard to separate the disruption caused by leaving the EU, the coronavirus pandemic and the war in Ukraine.
"There will be challenges and disruption as a result of fundamentally altering our relationship with the EU," he said but added that it was too soon to say whether or not that is going to be to the UK's long-term economic disadvantage.
He said the government was determined to take advantage of the opportunities provided by Brexit, pointing to plans for the regulatory regime of the financial services, life sciences and the green economy.
He also insisted the government did not want to make any fundamental changes to the UK's relationship with the EU, arguing that the country had settled on the right approach.
The message was reiterated by No 10 who said Mr Sunak was "categorical" the deal would not be fundamentally changed.
Specifically the Downing Street spokesperson said there would be no reintroduction of freedom of movement, no "unnecessary" payments to the EU and "nothing that limits the UK's freedom to do trade deals".