DUP leader Arlene Foster has said she believes Boris Johnson is focused on finding a Brexit deal that works and rejects the Irish backstop.
The party met with the prime minister in Downing Street on Tuesday.
Mrs Foster said that Mr Johnson had set out to the European Union why a Northern Ireland-only backstop would be anti-democratic.
“We do believe that he is in the space of trying to find a deal,” she told BBC Radio Ulster on Wednesday.
“It’s not just the DUP that rejects the backstop, it’s a much wider coalition that rejects the backstop.
“What we need to do now is reject the backstop, move on and find a deal that works.
“That’s what I’m focused on and I think it’s what the prime minister is focused on as well.”
The backstop is the insurance policy to maintain an open border between Northern Ireland and the Republic of Ireland after Brexit, until a wider solution is found.
Mrs Foster said the government is “exploring” an all-island food standards zone as part of a solution to replace the backstop.
She denied that the DUP’s influence with the prime minister had waned after he lost his parliamentary majority.
The DUP had been propping up the Conservatives in a confidence-and-supply pact since June 2017, with the votes of its 10 MPs giving the government a majority to get legislation passed in Parliament.
However, last week Mr Johnson lost his majority after 21 Conservative rebels had the whip removed for voting against the party on Brexit legislation.
It means he no longer requires the DUP’s votes, but Mrs Foster said her party has a “much wider bond” with Mr Johnson than just the political arrangement.
She said she believed the prime minister was true to his word in ruling out a Northern Ireland-only backstop.
There are suggestions that the government is contemplating such a proposal in order to ensure the UK leaves the EU with a deal by 31 October, but Mrs Foster said that was not true.
She also dismissed suggestions that a solution could end up being the backstop by another name, adding: “It’s not just a case of tampering with words.”
‘Abundance of proposals’
The prime minister has insisted he will not seek an extension to the Brexit deadline if there is no agreement with the EU.
In Dublin on Monday, Mr Johnson said he had an “abundance of proposals” to replace the backstop.
The idea of a NI-only backstop was first suggested early in the Brexit negotiations.
Former PM Theresa May rejected it in 2018 because she relied on the votes of the 10 DUP MPs in Parliament.
The Irish government has said it is willing to look at a “Northern-Ireland specific solution”.
On Tuesday, Ireland’s EU Commissioner Phil Hogan told RTÉ that there is “movement” happening on both sides of the Brexit negotiations.