According to French media, Mr Macron privately made disparaging comments about Mr Johnson as tensions ran high over the migrant crisis in the Channel.
Satirical newspaper Le Canard Enchaîné reported that Mr Macron called Mr Johnson a “clown” and a “knucklehead”, the Times and the Telegraph reported.
Asked on ITV’s Peston programme about the comments, Work and Pensions Secretary Therese Coffey said they were “news to me”.
“I’m surprised to hear that. I’m conscious that we have a shared mission in trying to make sure that the people smuggling gangs are really brought to justice,” she said.
When it was put to her that the development was “troubling”, Ms Coffey added: “As I say, I’m surprised to hear that and disappointed, openly.
"I’m sure that we can continue to try and work together to tackle this. But the prime minister wrote formerly to the president last week and… I hope that we’ll get a formal response back.
“People smugglers, they don’t care if people live or die. They just want their money. And we’ve got to try and work this through, not only between our two shores, but actually tackling this in the first place. And I’ve got confidence that Priti [Patel] is trying to make those inroads right across not just Europe, but also in our more international communications as well.”
Ms Coffey's comments were echoed by business minister George Freeman who said the alleged comments were “pretty unhelpful”.
Speaking to Sky News, Mr Freeman said: “I think we are into pantomime season, aren’t we? And there is a French election coming.
“It is a pretty unhelpful word. Of course, the prime minister isn’t a clown, he is the elected prime minister of this country with a very big mandate, leading this country through the pandemic."
The Times reported that a senior UK government source said: “The prime minister continues to be a staunch advocate for the strength of the UK-French relationship.”