On Monday, the US completed the reimposition of all US sanctions against Iran which had been relaxed under the P5+1 nuclear deal. President Trump withdrew the US from the deal in May, and there was a six month window after the announcement before sanctions could be resumed.

According to national security adviser John Bolton, this is only the beginning. During a Monday interview with Fox Business, Bolton insisted that the administration plans to “even go beyond this,” and that more sanctions are coming.

He was not specific on what that means, but Bolton did say that the administration would not “be content with going back to the level of sanctions that existed under Obama in 2015.” The 2015 sanctions were nearly a full blockade of Iran, and it’s not clear what additional sanctions are even possible.

Administration officials are also claiming they cost Iran “billions of dollars” in oil revenue since May just on the threat of sanctions. They claimed the announcement took one million barrels of oil a day off the market.

It’s not clear this is true, however, as while some companies did indeed back away from trade with Iran during that period, there is no good information on how many planned to buy oil, let alone that Iran wasn’t able to simply sell that oil to someone else.