Possibly Trump reminded the SA leader of the dollars for oil contract and the fact that Qatar is settling their bills to China for Yuan. We know what happens to those that try that option.
http://www.thenational.ae/business/banking/uae-and-qatar-lead-region-in-yuan-payments-to-china
There is also the joint gas field with Iran. If the pipeline to Syria/Europe/Russia is ever built. Co-mingling Qatari gas and Iranian gas has two benefits. Iran and Qatar get their gas into Europe and Russia beats the sole gas supplier obstacle that the EU is always bringing up. The co-mingled gas from Iran and Qatar gets mixed with Russia gas which defeats the EU demands. What the % mix will be unknown except to a few.
It also, if delivered through the NordStream 1 or 2 or a modified South Stream routes, nullifies other EU demands.
Probably not priced in US$ either.