New Regulations for Foreign Banks and Governments

Kathy Bostjancic was recently quoted in this article
Economic Pieces

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She comments that  the reduction of repo treasury supply is a result of the regulations and constraints imposed on dealers’ balance sheets. She states that the Fed and other regulators want to prevent repeating the ’08 financial crisis where investment banks relied heavily on repo for short-term funding, and that this played a significant role in the financial crisis. This frames the entire article.
In essence the US Treasury wants to increase control of their destiny by asking repo and treasury traders to voluntarily report holdings. There is fear, however, that this added regulation will result in significantly less investment. 
Foreign states will be especially reluctant to report. China and Japan, for example, hold the most treasury bonds and it is detrimental to upset them in any way. 
The US Treasury, on the other hand, believes that since reporting is voluntary there will not be a significant negative effect from the new regulations.