Microsoft's president urges other tech firms to accept responsibility for the effects of their work.
Microsoft's president has called on the US to end a ban on it supplying Huawei with Windows software for the Chinese company's computers.
Huawei was blacklisted by the Trump administration in May over claims it posed a threat to the US's security.
That prevents American companies from providing it with their latest tech.
Brad Smith said he did not believe the US's security would be "undermined" by letting Huawei's customers use its operating system or Office apps.
"Governments around the world are going to address their national security needs," he told BBC News.