Nigel Farage will appear on stage with Donald Trump in the US to discuss "the Brexit Story", says an adviser to the former UKIP leader.
The Republican presidential nominee is due to campaign on Wednesday evening in Jackson, Mississippi, as Mr Farage visits the southern US state.
Mr Farage is expected to talk about how the "anti-establishment beat the establishment" to bring about Brexit.
Raheem Kassam, a former UKIP adviser, told the Press Association that Mr Farage will not endorse the Republican candidate.
"As I understand it," Mr Kassam said, "I think the plan is for him to speak ahead of Trump's speech, and basically just to walk the audience through the Brexit campaign and how the anti-establishment beat the establishment."
Ahead of the appearance, Mr Farage appeared on the radio show SuperTalk Mississippi.
He railed against the political classes and compared Mr Trump's popularity with the "silent majority" of the British people who voted for Brexit.
He said that just as Brexiteers mobilised a "people's army", so too can Mr Trump in the United States.
Mr Farage told the show: "I'm telling a story about Brexit, and it's a story that if the grassroots Republicans pick up, and if they understand that what they've got to do is not just sit in their armchairs, they've got to get out, put their walking boots on, deliver leaflets, go out and meet these people in the communities.
"In a sense what I'm saying is that we mobilised a people's army in the United Kingdom that went out and spoke to everybody and got them down the polls, the same thing can happen here."
Mr Farage accused President Barack Obama of having "talked down to the British people" by telling them how to vote in the referendum.
Many Trump supporters have voiced nationalist, anti-globalisation, anti-establishment views, which have been echoed among many who voted for Brexit.
Mr Trump caused a stir last week with a cryptic tweet in which he said: "They will soon be calling me MR BREXIT!"
The real estate businessman supported June's UK vote to leave the European Union and described it as "the people taking the country back".
During a visit to his golf resort in Ayrshire, Scotland, in the aftermath of the referendum, Mr Trump said the result was a "great thing".