The Na h-Eileanan an Iar MP raised the issue in the House of Commons, arguing that the eligibility rules should be relaxed to ensure more households can access support before the scheme closes in September.

The £300 payment was introduced following a spike in heating oil prices after US strikes against Iran earlier this year. The UK Government provided £4.6 million for Scottish consumers, with the Scottish Government adding a further £5.4 million.

However, responding to questions from Mr Crichton, UK Energy Minister Martin McCluskey confirmed that just over £1 million has so far been claimed through the Scottish scheme.

Mr Crichton said the low uptake showed the current criteria were preventing people from accessing support.

"Given that only 10 per cent of the £10 million fund has been allocated, it is time to change the criteria for the scheme," he said.

At present, the Advice Direct Scotland scheme is open to households that use heating oil and receive pension or income-related benefits.

Mr Crichton said he had heard that more applications were being rejected than approved under the current rules.

He also pointed to the scheme's original commitment to support households with a priority need for heating because of their geography or rurality.

"All of the Western Isles can be described as very rural or remote, which are the qualifications for eligibility under this geography and rurality definition," he said.

The MP highlighted the islands' heavy reliance on heating oil, noting that almost half of households depend on it to heat their homes, while the Western Isles also experience some of the highest levels of fuel poverty in Scotland.

"Given that almost half of island households are dependent upon heating oil and that we have the highest rates of fuel poverty in the country, support should be directed where it is most needed," he said.

Mr Crichton said he would be pressing both Advice Direct Scotland and Scottish Government ministers to widen access to the fund.

"I will be approaching Advice Direct Scotland and ministers again about extending this scheme to all island households dependent on heating oil," he said.

"Advice Direct Scotland and SNP ministers should step up to get this money out the door instead of leaving consumers high and dry when it comes to heating oil support."

He also encouraged anyone who believes they may qualify to apply for the £300 payment before the scheme closes and to contact his office if they require assistance with an application.