Regarding Trump freezing Venezuelan assets, according the UK paper TheGuardian.com, is based on an order signed on Monday but I haven’t found that order yet (not on Whitehouse.gov).
~~~~~~
The ban on Americans doing business with Venezuela’s government takes effect immediately.
“All property and interests in property of the Government of Venezuela that are in the United States ... are blocked and may not be transferred, paid, exported, withdrawn, or otherwise dealt in,” the executive order says.
https://www.theguardian.com/us-news/2019/aug/06/trump-freezes-all-venezuelan-government-assets-in-us
The order, signed by President Trump on Monday, cited Maduro’s continued “usurpation” of power and human rights abuses by those loyal to him.”