Arlene Foster will address Conservative party conference delegates at a DUP-organised reception in Birmingham on Tuesday.
The DUP leader said it will be an opportunity to explain why Northern Ireland should leave the EU on the same basis as the rest of the UK.
Conservatives began their annual conference at the International Convention Centre in Birmingham on Sunday with party chairman Brandon Lewis claiming Labour leader Jeremy Corbyn was “unqualified and unfit” to govern the country.
Mrs Foster, DUP deputy leader Nigel Dodds and Lagan Valley MP Jeffrey Donaldson are due to arrive at the conference on Monday.
The DUP entered into a “confidence-and-supply’ agreement with the Conservatives in June 2017 – meaning the government could be assured of the DUP’s ten votes on certain issues in return for a financial package to support key services in Northern Ireland.
Ahead of Tuesday afternoon’s DUP reception, Mrs Foster said the confidence-and-supply deal was “delivering” for the entire United Kingdom, and that she was looking forward to attending the conference.
“It is an opportunity for us to engage with fellow unionists from throughout the UK and beyond,” she said.
“Whilst we will be hosting our own event at the conference, we will also be using the time to engage with many other delegates to ensure the needs of Northern Ireland are properly understood.”
Mrs Foster added: “The DUP/Conservative confidence-and-supply agreement is delivering not only the additional £1bn for roads, schools and hospitals in Northern Ireland but also a better deal for the entire United Kingdom.
“Our event marks the fact that we work together for the entire United Kingdom as unionists. It will also be an opportunity to explain why we need and want to leave the EU on the same basis as the rest of the UK.”