Stormont's Finance Minister has said there is "no guarantee" households in Northern Ireland will directly receive a promised £400 discount on their energy bills without a functioning Executive.
Conor Murphy said there were "challenges involved" with no power-sharing administration in place but he was determined to work with the Treasury on a solution.
Households in Northern Ireland will receive financial support as part of a £15billion UK government package to address the cost-of-living crisis.
Read more: Fuel payment scheme cannot be reopened without NI Executive, says Communities Minister
A one-off payment of £650 will be given directly to the lowest income families in two instalments, with the first due in July and the second following in the autumn.
There will also be an energy bill discount of £400 for every household in the autumn under the measures announced by Chancellor Rishi Sunak - funded with a £5billion tax levied on oil and gas giants.
Northern Ireland has no fully functioning power-sharing Executive or Assembly in place as the DUP is blocking their formation in protest over Brexit's Protocol.
Most ministers from the previous administration before recent elections remain in post in a caretaker capacity but they can only make limited decisions.
Mr Murphy has said there was "no guarantee" households in Northern Ireland would directly receive the £400 discount later in the year.
He said: "There are challenges involved in this because we don't have an Executive in place.
"The Treasury recognise it's not an acceptable situation and it would be far easier if the DUP stopped blocking an Executive.
"We will certainly work as best we can because we are determined to ensure the money goes to people who need it."
The absence of an Executive means it remains unclear when and how people in Northern Ireland will receive this discount.
If the funding was allocated through the usual Barnett consequential formula, the additional cash would likely need formal Stormont Executive approval before it could be spent.
However, the UK Treasury said it may not make the payment for Northern Ireland through this method because of the current political instability.
Mr Murphy said Northern Ireland would receive £14million as a Barnett consequential due to the extra funding announced by the chancellor for the Household Support Fund in England.
He said this brought the pot of unallocated Stormont funding requiring Executive sign-off to £435million.
The Sinn Féin minister said: "The additional £14million funding we will receive from the Household Support Fund cannot be allocated in the absence of an Executive.
"This now means there is a total of £435million which cannot be allocated to help families, workers and businesses with the cost of living and to support public services, particularly our health service."
Fuel poverty charity National Energy Action NI welcomed the chancellor's announcement to help tackle cost-of-living pressures.
But it said it was "deeply concerned" that struggling families in Northern Ireland may not have access to the full range of support measures available in Great Britain.
"There is a huge onus on our political leaders to ensure that much-needed emergency funding is allocated to those who need support," it said.
The UK support package came a day after Sue Gray's damning report into lockdown parties in Downing Street, leading to scepticism over the timing of the government's major funding announcement.
The Treasury said it would consider the options to ensure households in Northern Ireland receive the equivalent support to other parts of the UK.
However, it was unable to give a timeframe on when a decision would be made.
A Treasury spokesman said: "The Treasury said there was no timeframe on when a decision would be made, but that it wanted to implement it urgently.
"The UK government believes it is vital that the Northern Ireland parties form an Executive as soon as possible, to give the people of Northern Ireland a stable and accountable government.
"We have not ruled out the Barnett consequential as the best way to get the support we have announced today to the people of Northern Ireland.
"But given the situation with the Executive, we want to consider other options to ensure Northern Ireland gets equivalent support."
Read more: Fuel payment scheme cannot be reopened without NI Executive, says Communities Minister
Read more: Cost-of-living crisis: Northern Ireland family 'using kitchen hob to heat their home'
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