The Mirror claims Mr Sunak, who they dub a “helicopter addict”, took a half an hour flight from Wellington Barracks in Westminster to the seaside town – a journey of less than 60 miles.
The CO2 emissions of such a journey are estimated to be 18 times higher than if the same journey was made by car.
Downing Street did not confirm if the reports in the Mirror are correct but said: “The Prime Minister regularly uses all forms of travel.
“His travel plans will vary and are always decided with consideration to the most efficient and best use of his time, in the interests of the taxpayer.”
READ MORE: Updates as Prime Minister Rishi Sunak visits Clacton
Last month Mr Sunak said the Government remains committed to achieving its net zero emissions target.
UK emissions are supposed to fall by 68 per cent compared with 1990 levels by the end of the decade, but the Climate Change Committee said there remains a “substantial policy gap” in achieving this.
Earlier this month Chancellor Jeremy Hunt admitted he flew to Manchester from London for the Conservative Party conference rather than taking the train, blaming industrial action.
Why was Rishi Sunak in Clacton?
The Prime Minister visited Clacton on Wednesday to visit projects supported by Levelling Up funding.
Alongside Tendring Council leader Mark Stephenson and Essex County Council deputy leader Louise McKinlay, Mr Sunak visited Clacton Library which is due to be redeveloped as part of Clacton’s Levelling Up project.
The project will see millions of pounds invested to create a new gateway into the town, providing new community facilities including a library, learning centre, business units, homes, and improvements to public spaces.
Mr Sunak also observed a maths class for adults at the library and visited the Essex Pedal Power cycling initiative.