The Prime Minister’s official spokesman said Boris Johnson, who is back in No 10 today following his holiday in Slovenia, would be speaking to Chancellor Nadhim Zahawi to ensure that support measures due to come into effect later in the year remained on track.
However, the spokesman said any further measures would be a matter for the next prime minister.
“Clearly these global pressures meaning challenging times for the public,” the spokesman said.
"The Government recognised that the end of the year will present wider challenges with things like changes to the [energy] price cap.
“That is why, at the start of the summer, we introduced a number of measures to help the public. Clearly some of the global pressures have increased since that was announced.
“By convention it is not for this Prime Minister to make major fiscal interventions during this period. It will be for a future prime minister.”
Mr Brown had urged Mr Johnson to unite with Tory leadership hopefuls Liz Truss and Rishi Sunak to prepare and agree on an emergency budget – or face growing pressure to recall Parliament and force them to do so.
Cobra, or COBR (Cabinet Office Briefing Rooms), is a UK Government civil contingencies committee that meets to discuss matters of national emergency or major disruption.
Mr Brown claimed there was a “vacuum” at the centre of Government that had stopped it tackling the cost-of-living crisis.
The former prime minister said on Good Morning Britain: “There’s got to be someone in charge. And it’s not just that they’re asleep at the wheel – there’s nobody at the wheel at the moment.
“You’ve got Boris and his chancellor who have been on holiday, and then you’ve got the two leadership candidates on the campaign trail.
“What’s happening at the centre of Government is there is a vacuum and it’s got to be filled immediately if we’re going to protect people by October.
“I know from my own experience, you’ve got to act quickly to deal with the benefits and tax issues if you’re going to get the changes in by the time you want them to be in.”
The former PM added: “The facts right now are grim: four in every five pensioners, four in every five single parents and four in every five large families face fuel poverty – that’s when their energy bills come to more than 10 per cent of their weekly incomes.”
Mr Brown said waiting until next month to introduce an emergency budget to tackle the cost-of-living crisis would be “too late” for those facing “unpayable” bills in October.
He said: “If you don’t act now, you cannot get the benefits to people by October 1.
“If you wait until after the new prime minister is selected, that will be too late to get benefits to people by October 1.
“It’s too late because people will be experiencing great hardship, an unbearable burden of unpayable bills in October.