Theresa May is to vow to renew the UK’s special relationship with the US “for this new age” as she prepares to meet Donald Trump for the first time.
She travels to Philadelphia later to address Republican leaders at an event attended by the US president.
She will tell them that after Brexit, a “sovereign, global” Britain wants to enhance ties with its “old friends”.
On Friday, Mrs May will be the first world leader to hold face-to-face talks with Mr Trump in the White House.
Post-Brexit trade opportunities, security and intelligence co-operation and the future of Nato are likely to feature significantly in the talks.
Mrs May has said her goal is to build on the historic relationship between the two nations, underpinned by their shared values and common interests.
But she has said she “won’t be afraid” to speak candidly to Mr Trump on matters where they disagree, having criticised remarks the businessman has made in the past about women and Muslims.