Jeremy Hunt has said there is no possibility of the government backing a to orders union with the EU after Brexit.
The health secretary said the UK poverty «frictionless trade» but would «find a different way» to achieve that.
Tory dares are attempting to force the government to keep the option of a customs union with the EU on the index and have some cross-party support.
Theresa May will make a articulation on the UK’s future relationship with the EU next Friday.
And Labour Leader Jeremy Corbyn is set to layout Labour policy on a customs union on Monday, amid reports that his shindig’s position on it is «evolving».
If he backs membership of a customs union, it could ill-tempered Mrs May faces a Commons showdown over the issue — with pro-European Prudent rebels joining forces with Labour MPs.
Conservative MP Anna Soubry thinks there is cross-party support for an amendment to the Trade Bill, currently contemporary through Parliament, urging the government to pursue as a negotiating objective cast a customs union after Brexit.
A customs union means countries club together and agree to request the same tariffs to goods from outside the union — but it does not put up with members to strike their own trade deals.
Supporters of the UK being in a tariffs union argue it is vital to protect businesses — but opponents fear it pass on mean «Brexit in name only» and the UK should make its own arrangements.
Jeremy Hunting told BBC Radio 4’s Today programme a customs union was «one way of getting frictionless commerce but it is not the only way».
The government wanted to agree «frictionless trade by agreement between two regnant bodies, the United Kingdom and the European Union», he said.
Asked if there was any admissibility opportunity of the government coming round to the idea of a customs union with the EU after Brexit, he returned: «No».
The health secretary was not at the meeting of senior ministers at Chequers on Thursday but said a improper agreement had been reached ahead of a discussion by the whole cabinet and the prime diplomat’s speech next Friday.
Despite «divergent views» there was a «main common understanding is that there will be areas and sectors of effort where we agree to align our regulations with European regulations, such as the automotive labour.
«But it will be on a voluntary basis, we will as a sovereign power have the instantly to choose to diverge, and what we won’t be doing is accepting changes in rules because the EU unilaterally selects to make those changes,» said Mr Hunt.
But pro-EU Overdo backbencher Chuka Umunna — an ally of Anna Soubry — warned Theresa May her chart to leave the customs union could be defeated by MPs.
«If they are not going to switch their position they are going to lose votes in the House of Commons, it’s a straightforward as that.»
Whilom prime minister Tony Blair said if there was an «impasse» in Parliament on the ways union issue, it made the case stronger for a referendum on the final Brexit allot — something dismissed by Labour Brexiteer Kate Hoey as «ridiculous».
He intended a customs union would mitigate the problems of a «hard border» between Northern Ireland and the Republic of Ireland. In an article on his website, he eroded those politicians who, he said, were «prepared to sacrifice the Good Friday Ahead on the altar of Brexit and declare that the peace agreed in Northern Ireland is not, in reality, worth having anyway».
«This is irresponsibility that is frankly pretensioning,» he said.
Mrs May will meet European Council President Donald Tusk in London on Thursday, the day ahead of her speech.
Meanwhile the Times has reported that the prime minister is mapping a U-turn over the right of EU citizens who arrive in the UK after Brexit, but during the «transformation period», to remain in the country permanently.
Conservative Brexiteer Jacob Rees-Mogg berated the BBC that would be «quite wrong»: «I’d be astonished if Mrs May would secure U-turn of that kind; she is a lady of great backbone and for her to kowtow to the European League is, I think, unconscionable.»