Prime Minister Boris Johnson tweeted: "We've got a great new deal that takes back control."
The two sides have been working on the legal text of a deal, but it will still need the approval of both the UK and European parliaments.
BBC chief political correspondent Vicki Young says the DUP will not support it.
The Northern Irish party earlier released a statement saying they could not back proposals "as things stand", and - after the PM's announcement - said their statement "still stands".
Vicki Young said senior DUP MPs have met in the Commons to discuss the deal, but will not vote for it.
Labour leader Jeremy Corbyn said the deal sounded "even worse" than what was negotiated by the PM's predecessor, Theresa May, and "should be rejected" by MPs.
But European Commission President Jean-Claude Juncker said it was a "fair and balanced agreement".
Both he and Mr Johnson have urged their respective parliaments to back the deal.
No 10 sources have told the BBC's political editor Laura Kuenssberg that Mr Johnson will later ask EU leaders to reject requests for an extension to the Brexit deadline of 31 October.
MPs passed a law in September that requires the PM to request an extension on 19 October if Parliament has not agreed a deal or backed leaving without a deal by that date.
MPs will later vote on whether to hold an extra sitting in the Commons on Saturday to discuss the next steps.
Cabinet Office minister Michael Gove said if the sitting was approved, the government would hold a vote on the deal.
He said he was "not contemplating defeat", but if the plan did not get the backing of MPs, the alternative was leaving without a deal.