Kwasi Kwarteng is facing calls for an official inquiry following a report that he attended a private champagne reception with hedge fund managers following his mini-budget.
The Sunday Times newspaper reported that the chancellor joined the gathering in Chelsea on 23 September and was said to have been "egged on" to pursue his plan of £45bn of unfunded tax cuts.
Those hedge fund managers present stood to gain from the collapse in sterling following the mini-budget.
Speaking to Sky News' Ridge on Sunday programme, Conservative Party Chairman Jake Berry denied that Mr Kwarteng discussed plans for future spending cuts at the event.
Mr Berry, who attended the event, said: "I certainly didn't hear him make those comments.
"I was there so I listened to what he said and what he talked about was his plan for growth."
Mr Berry added: "I can categorically rule out that in terms of the address he made to the group of people who were there as part of this normal treasurer's event, he did not give any insight into future plans and I'm sure in terms of his private conversations he didn't give any."
He said that the event's guests were broader than just hedge fund managers and also included property developers.
Mr Berry said these individuals "should be lauded" for supporting political parties and that the reception was part of the "normal drumbeat" of treasury events.
The Tory party chairman also noted that he believed Mr Kwarteng was "drinking a soft drink" at the do.
Also probed on the champagne reception, Liz Truss said Mr Kwarteng "meets business people all the time".
"I do not manage Kwasi Kwarteng's diary, believe me," the PM told the BBC.
Pressed on whether it would have been better if he had not attended since people are struggling with the cost-of-living crisis, Ms Truss said: "I get up every morning as prime minister thinking how can we make our country more successful, how can we reassure people, how can we help people get through these very difficult times and we do face difficult times...
"And that's what I'm focused on. That's what the chancellor is focused on and that is what the whole cabinet is focused on."
The Liberal Democrats have called for an inquiry into the matter.
The party's treasury spokeswoman Sarah Olney said: "While struggling homeowners saw their mortgage bills spiral, it seems the chancellor was sipping champagne with hedge fund managers profiting from the falling pound.
"How out of touch can you get? We need an official inquiry into this now."
A source close to the chancellor said: "Any suggestion attendees had access to privileged information is total nonsense.
"The Growth Plan published on Friday included a commitment to review our tax code to make it simpler, better for families and more pro-growth.
"The government's ambitions on lowering the tax burden are hardly a state secret."
The prime minister is set to face a wretched week at the Tory Party conference after the disastrous reaction to Mr Kwarteng's tax-cutting mini-budget last month.
But ahead of the official opening of the event in Birmingham which comes at the end of another tumultuous week for the Conservative Party, Ms Truss said she was sticking to her guns and that the tax cuts were essential to getting the economy to grow again.
A series of polls taken this week have shown a massive drop in popularity for the Tories and a record high for Labour following the mini-budget.
The latest poll from Opinium showed 55% of voters disapprove of both Ms Truss and Mr Kwarteng while Labour enjoyed a 19-point boost.
And 75% of all voters think they have lost control of the economy. When it comes to Tory voters, 71% think they do not have the economy under control versus just 24% who believe they do.
But despite the criticism and plummeting support, Ms Truss this morning doubled down on the decision to remove the top rate of income tax (45%) as "it's part of an overall package of making our tax system simpler and lower" - but admitted the policy was not discussed with the cabinet.
"It was a decision that the chancellor made," she told the BBC.
A spokesperson for the chancellor said: "As the PM said this morning, the 45p rate raises very little and makes our tax system more complicated.
"While the chancellor obviously makes all tax decisions, the prime minister and Kwasi are in lockstep on this."