DUP leader Arlene Foster has said that she is hopeful an agreement can be reached to restore power-sharing at Stormont before the summer.
Mrs Foster was speaking at Stormont after a meeting of party leaders on Thursday.
Talks are set to intensify next week after a positive meeting between the leaders, Secretary of State Karen Bradley and Irish Foreign Minister Simon Coveney.
Mr Coveney and Mrs Bradley said they will recommend to Prime Minister Theresa May and Taoiseach Leo Varadkar that a new talks process gets under way at Stormont next week.
Prime Minister Theresa May and Taoiseach Leo Varadkar are set to review the progress made between the parties at the end of May.
Mrs Foster said that she believed an agreement was possible, but cautioned that there was still work to do.
"Now we are really into the focused intense period and we are looking forward to engaging in that," the DUP leader said.
"I think the window is quite short because once we get to the summer we know that other pressures will come to bear so therefore we are up for trying to work intensively to try to find a way forward.
"We have duty now to come forward and to try to find a way forward."
Mrs Foster said that she believed there had been a shift from previous failed talks.
"I think this is for real. I think people are very much engaged," the Fermanagh and South Tyrone MLA said.
"Now we need to engage in a fulsome way on very critical issues, on issues that will be challenging, that will be difficult, but if we are to form a genuine powersharing administration then we need to deal with those issues. But it has to be done in way that is balanced and in a way that is fair."
Mr Coveney said there was "momentum" in the talks process, while Mrs Bradley said she was "positive that there is the right attitude and there is the right will there".
Sinn Fein President Mary Lou McDonald said that Thursday's meeting was "very positive" and that she believed outstanding issues could be resolved.
“It is decision time for the two governments and the parties," she said.
“Leadership and political will is required to have good government, inclusive government, stable government, a government which has room for every citizen. A system of government where agreements made, are agreements delivered.
“Broken promises are the reason we have broken politics. We need to fix that, I believe that we can."
However, Mrs McDonald stressed the need for an Irish Language Act and legacy issues to be addressed before any agreement can be reached.
SDLP deputy leader Nichola Mallon cautioned that the "difficult issues" still remained unresolved.
"It is very clear, anyone who went round the doors over the last two elections will know, that the people of Northern Ireland right across the north want their politicians back to work," she said.
"We are committing to doing that, that is our priority and it will remain our priority as we enter this next phase of negotiations."
Alliance Party leader Naomi Long said the working groups had made some progress "stress testing" proposals.
"But I think all of us recognise that at this stage we need to move on to a different stage in this process where it's actual direct negotiations with the party leaderships," she said.
"We are hoping that will be the case next week.
"I think people's expectations have been raised by the recent round of talks and now it's up to all of the parties to deliver."
Ulster Unionist leader Robin Swann said the "mood music" around the table was a lot better than he expected.
"There were no red lines throw out around the table, it was about how we get to the next step and what the next step actually looks like," he said.