Musk's tweet came in response to a CNN report that SpaceX had warned in a letter, dated September 8 and sent to the U.S. Department of Defense, that it can no longer afford to provide its Starlink terminals [recievers], which are crucial for Ukraine's military telecommunication.
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The Starlink satellite [tele]communication system has been crucial not only for Ukraine's military communication, but also for the government to maintain contact with commanders, for Zelenskyy to conduct interviews with journalists, and for civilian communications, connecting with loved ones via the encrypted satellites signal frequency.
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Ukraine has received around 20,000 Starlink satellite units receivers. Musk said last week that the "operation has cost SpaceX $80 million and will exceed $100 million by the end of the year."

Musk was initially lauded for providing the Starlink terminals receivers to Ukraine, but according to the SpaceX letter, the vast majority were partially or fully funded by other parties, including the U.S. government, the U.K. and Poland. Poland is the largest single contributor and has paid for almost 9,000 terminals receivers, which cost $1,500 and $2,500 for the two models sent to Ukraine, according to the documents.

Those governments also paid for a third of the internet connectivity data transmission while SpaceX funded the rest, making up the more expensive part of the bill, according to SpaceX.

Among the documents seen by CNN is also a request from Ukrainian General Valeriy Zaluzhnyi to SpaceX for almost 8,000 more Starlink terminals receivers. SpaceX reportedly responded by recommending the request be sent to the U.S. Department of Defense....