Peter Robinson and Martin McGuinness are working on a solution to the welfare reform crisis which involves no extra money, but instead spending existing funds in three years instead of six.
Theresa Villiers, the Secretary of State, will fly into Northern Ireland later this week after the budget debate. She hopes to chair a meeting which will formalise the agreement on Thursday.
While negotiations are ongoing narrowing the time frame is the new focus of talks.
One person who had been briefed on developments said "it is still being worked on but broadly there will be some adjustment to the regulations for payments and that would be reviewed in three years time.
The money for mitigation was always going to step up gradually as the new system came in.
"The argument now is that there is sufficient money in the pot to get us going. Then we can have a review in three years, see if we have it all spent and decide what to do next," they added.
Peter Robinson repeated yesterday that the deal on money had been done and there was no new money from the Executive. Sinn Féin also conceded that more money hasn't been found in the Northern budget or given by London.
Last week Martin McGuinness unexpectedly withdrew his party's support just three days after praising what they had achieved on the issue in a speech to his party's Ard Fheis. He accused the DUP of going back on commitments to protect the vulnerable. Mr Robinson called him "dishonourable" for changing his mind after reaching agreement.
Last night Conor Murphy of Sinn Féin said "both teams are continuing to make progress towards a deal. The priority for the Executive must be the protection of the most vulnerable in society; that certainly remains Sinn Féin's position."