The use of the term “announce” may have made the Saudi moves seem more public than they have been. Here are some links:

“UAE denies political motive in foreign exchange shift to euros”

“Wave of petrodollars hits UK“

This article, “Greenback tumbles against euro,” in discussing daily currency trading, made a more general comment about the Saudi posture:

“However, much attention was focused on the Saudi Arabian Monetary Authority, which was said to have bought somewhere between €1.5bn and €5bn worth of euros yesterday, selling dollars in the process.

“If true, this could simply be the ongoing diversification of dollar-denominated oil proceeds into other currencies. However, with King Fahd having died only days earlier, this inevitably led to rumours the dollar selling was, in part, politically motivated, possibly linked to a long-term plan to shift the riyal away from a dollar peg to a basket arrangement.”

Although per the SAMA trading, some of the dollar selling has been explicit, a lot of it appears to have been acheived via the rebalancing of their various equity/private equity/DFI investments, which can be presented to the US as having to do with the merits of the particular investment, rather than being largely or entirely motivated by a desire to move away from the dollar

brad setser