In a bid to present a unified front after a summer of Cabinet infighting, the Chancellor and International Trade Secretary said there will be a transitional “time-limited” period designed to avoid a so-called “cliff-edge”.
Their article, however, did not specifically outline how long that transitional period may last.
Yet both Cabinet members made clear they would not keep Britain in the single market indefinitely.
Mr Hammond and Dr Fox are representatives of the Remain and Leave wings of the Tory party.
They wrote: “We will leave the customs union and be free to negotiate the best trade deals around the world as an independent, open, trading nation.
“We will leave the single market, because there was a vote for change on June 23 and that is what we will deliver.
“We want our economy to remain strong and vibrant through this period of change.
“That means businesses need to have confidence that there will not be a cliff-edge when we leave the EU in just over 20 months’ time.
“That is why we believe a time-limited interim period will be important to further our national interest and give business greater certainty – but it cannot be indefinite; it cannot be a back door to staying in the EU.
“We are both clear that during this period the UK will be outside the single market and outside the customs union and will be a ‘third-country’ not party to EU treaties.
“But we are also clear that during this period our borders must continue to operate smoothly; goods bought on the internet must still cross borders; businesses must still be able to supply their customers across the EU and our innovative, world-leading companies must be able to hire the talent they need, including from within the EU.”
The joint article comes following Cabinet Brexit splits which surfaced as Prime Minister Theresa May departed on a three week holiday last month.
In Mrs May’s absence, Philip Hammond suggested that he wanted Britain to be able to trade freely with the EU for four years after Brexit.