Senior political figures at Stormont involved in efforts to resolve the row over welfare reforms say discussions have so far not produced compromise proposals.
However, it is expected that talks involving the two main parties in the power-sharing administration - the DUP and Sinn Féin - will continue tonight.
Sinn Féin's Martin McGuinness said on Sunday that he hoped a formula would be found by the middle of this week.
The dispute is over Sinn Féin's insistence that present and future welfare recipients in a number of categories must not lose money in policy changes.
But the DUP, the Ulster Unionists and Alliance say the Stormont budget, agreed last December, doesn't have the funds to cover such a commitment.
Earlier, Northern Ireland's Secretary of State Theresa Villiers, who chaired a meeting of the five main party leaders at Stormont, urged a settlement of the dispute.
Afterwards, she said she was encouraged that progress is being made but that it is essential that a resolution is reached.
She also warned that if there is no settlement, the package of measures agreed last December, including £2 billion spending power, new institutions on the past and the transfer of powers over corporation tax would be jeopardised.
Ms Villiers also said stalemate would create a revival of the serious budget cuts crisis which hit Stormont last autumn.
Last year's Stormont House Agreement included a £564m sum, to be provided over the six-year period up to 2021, for those affected by the changes in welfare payments.
DUP leader Peter Robinson says there is not enough money in the allocated budget to meet Sinn Féin's interpretation of how the reforms will be implemented.
He stated on Monday "there is no money tree growing at Stormont" and also said the British government was not prepared to provide additional funds.
Yesterday, Britain's Chancellor of the Exchequer, George Osborne, said he will exercise a veto over devolving Corporation Tax setting powers from Westminster to Stormont until the welfare reforms dispute is settled.
It is understood that one of the options being discussed by the Sinn Féin and DUP delegations is to agree on a deal for a shorter period, such as three years instead of six years, with a review clause built in and to adjust the figures for that arrangement.
Mr McGuinness, Northern Ireland's Deputy First Minister, said on RTÉ's This Week on Sunday that he was hopeful a compromise agreement might be reached by the middle of this week.
Since taking office in 2010, Britain's Conservative/Liberal Democrats coalition has implemented significant spending cuts, including reductions in welfare provisions.
But Northern Ireland's power-sharing administration has, up to now, refrained from adopting such policies.
The British government has reduced Northern Ireland's block grant and indicated that further reductions will follow.
The shortfall in transfers from Westminster is the reason why the Stormont executive is faced with the most challenging series of budgetary decisions since the restoration of power-sharing.
