QATARWorlds largest LNG producer...
This could go either way.
The up case: Qatar gas distribution is lowered and thus prices go up as USA wants a higher price as they will fill the void.
OR
One of the main reasons gas was going down already was because this was a pre-emptive move and lower prices are meant to hurt QATAR much like lower gas is to hurt Russia, Iran.
I could be convinced on either.
FWIW. Spot prices have not changed since the announcement.