The CNN link in NOEL's x.com post uses the words "American military contractors".
All other x.com blog posts that I have read also refer to "American military contractors".
Here's my take...mostly guesswork.
One or all of the military aid packages includes provisions that American military contractor corporations (Raytheon/Lockheed Martin) are prohibited from establishing subsidiaries in Ukraine.
This was probably done to gain enough votes to pass the legislation required for the aid packages.
The most cost effective way to support Patriots & F-16s would be for the OEMs to establish Ukrainian subsidiaries who would hire qualified personnel to support their respective systems.
OEM contractors routinely do this for the U.S. military.
Unfortunately doing this in a war zone is the highest risk option.
If legislation is required, this will be a tough sell.
JMHO
The original story said “lifting a de facto ban on American military contractors deploying to Ukraine, four US officials familiar with the matter told CNN, to help the country’s military maintain and repair US-provided weapons systems”.