ARLENE Foster said she had a "useful discussion" with Theresa May as she confirmed support for the government ahead of last night's confidence vote.
The DUP leader said she had indicated during a meeting in London, which was also attended by the party's Westminster leader Nigel Dodds, that her party "will act in the national interest".
But she added that the issue of the backstop, the main sticking point for the DUP in Mrs May's rejected Withdrawal Agreement, "needs to be dealt with".
In a statement issued after the meeting, Mrs Foster said: "These are critical times for the United Kingdom and we have indicated that first and foremost we will act in the national interest.
"Lessons will need to be learned from the vote in Parliament.
"The issue of the backstop needs to be dealt with and we will continue to work to that end."
While the DUP's 10 MPs voted against the Withdrawal Agreement on Tuesday, Mrs Foster confirmed the party would vote in support of the government last night "so that we can concentrate on the real challenges ahead of us".
There will be "further engagements in the coming days", she added.
Speaking to the Press Association Mrs Foster said she told Mrs May her view is that "we should use the scale of that (Tuesday's) defeat to go back to Brussels and argue very strongly for the backstop to be looked at again and dealt with in a meaningful way so that we can get a withdrawal agreement that works for the European Union, but also works for the United Kingdom as a whole".
She added: "If we want a deal, and we do want a deal, and if Europe wants a deal then let us come back to the table and get that deal.
"It's not a question of opening up the whole withdrawal agreement. It is dealing with that single issue of the backstop."
