US officials told the Wall Street Journal that Huawei had access to law enforcement tools for wiretap-style monitoring of calls.
It comes a day after the US department of Justice unveiled fresh charges against the company.
Huawei said the new indictment had “nothing to do with facts and reality”.
The Chinese company makes phones and other popular products – but also builds critical communications infrastructure.
The Wall Street Journal’s report this week was about “lawful interception” interfaces, which allow law enforcement with an appropriate court order to monitor communications.
The report alleged that Huawei had secretly given itself the ability to access those tools without mobile phone companies knowing.
Allegations are ‘a smokescreen’
John Suffolk, Huawei’s global cyber-security and privacy officer, told reporters the idea that Huawei had access to the special “lawful intercept” equipment was completely untrue – and that the company did not even make such devices.
“We have no access to this equipment, we don’t know what call or information is being intercepted, we don’t know when it is intercepted. All we do is provide one side of the box which is blind to what’s happening on the other side of the box,” he said.