Asked about an ambition outlined in the 2019 Conservative manifesto to complete an agreement within the first three years of Government, Mr Sunak argued that the war in Ukraine and the pandemic meant that the "macroeconomic situation" had changed.
He told broadcasters on his trip Washington: "Since then we’ve had a pandemic, we’ve had a war in Ukraine, and that has changed the macroeconomic situation. The right response to that is ensure that we’re focusing our engagement economically on the things that will make the most difference."
He added: "Actually, what I’ll be talking to President Biden about today is how can the UK and the US work together to ensure security for our citizens? I think that’s the thing that we should be focusing on right now."
A free trade deal was not expected to be a significant issue on the agenda, if at all, for the discussions between the two world leaders in the Oval Office.
Shortly before the June 2016 In/Out referendum, the then US president Barack Obama warned that the UK would be at the “back of the queue” for a trade deal with the US if the country chose to leave the EU.
Brexiteers angrily criticised his warning which has so far turned out to be true, with such an agreement believed now to be on the back burner at least until after the next General Election in Britain, expected in 2024.
Labour leader Sir Keir Starmer said the Conservatives had failed to secure a trade agreement with the US.
Sir Keir said: "In 2019, the Conservative Party had in their manifesto that they'd have a trade agreement with the US by 2022. So, it's clear they've failed on that promise amongst many other promises.
"But that's not the only failure. They've got no strategy, they've got no way of taking the country forward, and what we need is an industrial strategy, a plan for growth.”
Economists say Brexit will cost workers in the UK arounad £1,300 a year, compared to if the country had stayed in the European trading bloc.
The Government has trumpeted trade deals with other countries but they amount to only a fraction of the business done with EU nations which has been hit by the UK splintering away from the major trading bloc.
Farming chiefs and former Environment Secretary George Eustice have also criticised a trade pact struck by the Government with Australia, which they say is biased against the agricultural sector in Britain.
The Brexiteers’ pledge that quitting the EU would allow Britain to take back control of its borders is also in tatters with net legal migration having risen to more than 600,000 a year, and thousands of people risking their lives to cross the Channel in “small boats” to reach the UK.