Theresa May and Donald Trump will begin talks on a new UK-US trade deal this week
The Prime Minister is to discuss reducing barriers and costs between the two nations when she meets the new US President at the White House on Friday.
Visa restrictions for trans-Atlantic business travel could also be eased under the deal, it has emerged.
Mrs May is expected to be the first national leader to meet President Trump.
Her spokeswoman said: "You can expect the Prime Minister to be very clear during her US visit about the benefits of free trade and championing them and wanting to look at what more can be done to increase that, while also looking at how we address the concerns there have been about whether the benefits are being spread to as many people as they could be."
The Prime Minister said on Sunday that Mr Trump was looking for "early" talks on a free trade deal despite concerns over his "America first" strategy.
Her spokeswoman played down suggestions that the "America first" strategy set out in Mr Trump's inauguration address last Friday might be an obstacle to a successful trade deal for the UK.
He has signalled his commitment to Nato
In the address on the steps of the Capitol, the new president said that "every decision on trade … will be made to benefit American workers and American families", protecting the US from "the ravages of other countries making our products, stealing our companies and destroying our jobs".
Asked about the comments, Mrs May's spokeswoman said: "With the leader of any country, you can expect them to look at how they are putting their country's interest as the top priority on their list. We are clear that we will be pursuing Britain's national interests."
Theresa May will meet the President at the White House on Friday
Mrs May will also stress the "importance of Nato as the bulwark of our defence" during their talks. It follows a suggestion from the new president that the trans-Atlantic security alliance has become "obsolete".
Mr Trump earlier this month claimed Nato was not "taking care of terror".
He also criticised some Nato member states for not meeting the the target of spending 2% of GDP on defence.
But he has also insisted that Nato is still "very important to me".
The best photos from Donald Trump's historic inauguration
Mon, January 23, 2017
The inauguration of Donald Trump as the 45th President of the United States will mark the commencement of the four-year term of Donald Trump as President and Mike Pence as Vice President. A public ceremony will be held on Friday, January 20, 2017.
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President Donald Trump waves as he walks with first lady Melania Trump and son Barron during the inauguration parade.
Mrs May's spokeswoman said: "She will be clear about the importance of Nato as the bulwark of our defence and the need for the alliance to effectively counter the biggest threats of the day, what that means in terms of evolving to deal with different threats and what that means in terms of the contributions countries make within the alliance."
Mrs May spoke by phone on Sunday with Nato secretary general Jens Stoltenberg and told him she would be taking these messages to Washington, said the spokeswoman.
The Prime Minister's spokeswoman played down concerns over Trump's 'America first' strategy
"From the conversations the Prime Minister has had with President Trump already, he has signalled his commitment to Nato," the spokeswoman added.
The Oval Office summit will also examine global issues such as tackling terrorism, the Syrian civil war and relations with Russia.
Mrs May said being the first world leader to hold talks with Mr Trump is the "biggest statement" she can make about the global role of women.
They will discuss reducing barriers and costs between the two countries
The Prime Minister will travel to the US on Thursday when she will become the first foreign serving head of state or government to address the annual congressional Republican retreat, when it gathers for its 30th anniversary in Philadelphia.
Her early meeting with the president will be seen as a major coup after an uneasy start to relations with Mr Trump following November's election.