The Obama Administration reportedly decided to withhold sanctions against Iran over ballistic missile testing on fears that it would damage their ability to negotiate a prisoner exchange. After the exchange happened yesterday, however, the US went ahead with the sanctions anyhow.

The move is likely to fuel new acrimony with Iran, and indeed with other P5+1 member nations, coming less than 24 hours after the US had removed the nuclear sanctions against Iran. Iranian officials have argued the new sanctions would violate the letter and spirit of the nuclear deal.

Indeed, that may be the case. The sanctions are based on UN Security Council resolutions forbidding Iran from developing ballistic missiles capable of delivering a nuclear warhead, which suggests the resolutions to be part of the now resolved issue of Iran’s nuclear program. Iran has also argued that the missiles in question aren’t capable of delivering a nuclear warhead at any rate, meaning they aren’t covered by the resolutions.

The other P5+1 nations all seem to agree, and it was only the US that complained at all about the tests, let alone going so far as to impose new sanctions against Iran within a day of lifting the sanctions against them.

The new sanctions aren’t as broad as the originals, of course, but will still serve as a slap in the face after Iran made the P5+1 deal and then went the extra mile to implement every portion of it months ahead of schedule.

That’s likely to be a costly decision for the US, as Iran is planning to use much of its newly unfrozen wealth to modernize its economy, and some major international corporations could be in for some big contracts in that regard. New US sanctions are likely to push the US companies to the back of the line in competing for such deals.