How Can I Import Certificate .SST File Into A GPO?

We're in a semi disconnected environment and I need to import an .SST file monthly with current root certificates and import the file into a Group Policy Object for distribution.

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I've been doing it manually for a few months but thought it'd be a fun little thing to automate as I get started with PoSh.

Here's what I have so far and it seems to work until the last step when I need to import the .SST into the GPO.

#Establish variables
$TodaysDate = Get-Date -Format yyyyMMdd
$FileNameFormat = "roots" + $TodaysDate + ".sst"

#Download certificates using certutil on UpdateServer.fqdn.com
e:\certutil.exe -generateSSTFromWU roots.sst

#Rename SST with today's date
Rename-Item .\roots.sst -NewName $FileNameFormat

#Copy to Certs dir with today's date
Copy-Item .\$FileNameFormat '\\FileServer\certs\'

#Import into 'Certificates root' GPO

Computer Configuration\Policies\Windows Settings\Security Settings\Public Key Policies/Trusted Root Certification Authorities.

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Is there a way to import the certificates into a GPO with PS?

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*Edit Code Block instead of Inline Code.