Work will begin on preparing the ground for a post-Brexit trade deal with the United States when the International Trade Secretary flies into Washington.
Liam Fox will meet trade representative Robert Lighthizer for two days of talks at the first UK-US trade and investment working group.
European Union rules mean the UK cannot sign a deal until after it has quit the bloc but the discussions will pave the way for a future potential free trade agreement.
Mr Fox said: "The first meeting of the UK-US trade and investment working group is the start of the next chapter in our special relationship.
"Although it's too early to say exactly what would be covered in a potential deal, the working group is the means to ensure we get to know each other's issues and identify areas where we can work together to strengthen trade and investment ties.
"Our work as an international economic department has never been more important and our exit from the European Union offers an unprecedented opportunity to reshape our independent trading ambitions and build on the already strong trading relationship with our single largest trading partner - the US".
The Government was urged to ditch a ban on imports of chlorinated chicken to send a symbol that Britain was willing to make sensible compromises to reach a speedy trade deal.
Free market think tank the Adam Smith Institute said American chickens are more than a fifth cheaper than British ones and claimed three entire chlorine-washed birds would have to be eaten every day for an extended period to risk harm.
It warned that poultry market access is likely to be a take-it-or-leave-it condition of an agreement between the UK and US.
In a report it said there is a wealth of evidence about the safety of the chicken, including an assessment by the European Food Safety Authority that four types of chemical rinse, including chlorine dioxide, "would be of no safety concern".
Author Peter Spence said: "Trade critics like to suggest that signing a deal with the USA will mean that Brits will be forced to eat unsafe produce. In reality, chlorinated chicken is so harmless that even the EU's own scientific advisers have declared that it is 'of no safety concern'.
"Agreeing to US poultry imports would help to secure a quick US trade deal, and bring down costs for British households. European opposition to US agricultural exports has held up trade talks for years.
"By scrapping the ban on chlorinated chicken imports, the Government will send a signal to potential trading partners across the globe that the UK remains an open-facing and free trading nation."
Mr Fox will also meet commerce secretary Wilbur Ross, give a speech at the American Enterprise Institute and host a breakfast with members of Congress on the trade tour before heading to Mexico for talks with economy minister Ildefonso Guajardo.
A Department for International Trade source said it was too early to discuss specific trade issues, such as chlorine chicken.
"Specific agricultural issues are a long way down the road and are not being discussed at this stage," the source said.
Theresa May's official spokesman said it was too early to discuss specific details of any trade deal, such as the issue of chlorinated chicken.
The spokesman was challenged at a regular Westminster media briefing over whether the Government was guaranteeing to maintain EU-level food standards after Brexit.
He said: "Our position when it comes to food is that maintaining the safety and public confidence in the food we eat is of the highest priority Any future trade deal must work for UK farmers, businesses and consumers."
Labour MP Ben Bradshaw, a leading supporter of the Open Britain campaign, said: "The Government is putting the Fox in charge of the hen coop when it comes to food safety.
"This row about chlorine chicken is a direct result of the Government's decision to leave the single market. They are so desperate for new trade deals to make up for some of the losses that they seem ready to compromise on the safety of the food we eat.
"The Government must not water down rules that protect consumers, and neither should they follow any policy that undermines our own farmers.
"If they want to boost our economy, they should do so by keeping Britain in the single market, rather than selling ourselves short in desperation for new trade deals."
The International Trade Secretary said any transitional deal with Brussels after Brexit would involve being outside the single market and customs union, but could include "some of the practices" of the arrangements.
"We will be leaving the European Union at the end of March 2019 and there can be no implementation, no transitional period, unless we are out of the European Union at that point," Mr Fox told BBC Radio 4's World at One.
"We will be out of the European Union, we will be out of the single market and out of the customs union.
"We may decide to implement some of the practices of those for a period of stability, which we believe is in the interest of UK business and our overseas investors, but we will not be inside the customs union or inside the single market which are legal entities which are part of the European Union."