Not only those countries...
all the countries that used to have the "privilege" of getting a visa on arrival...I recieved as well a E-mail from my embassy.Indeed all the visa have to be requested through Qatari embassies in respective countries BEFORE travelling to doha, or Via hotels or maybe Families members in Doha.
I can "smell" that this is a direct consequence of the killing of an Hamas member in Dubai few months back by the Mossad using European Passport....
.
GCC Autorities have indeed realised that we might have "Mossad" people living in the gulf area using european(western) passport.
Another step "Forward"...
When i think Qatar Bids for the World Cup 2022....
Good luck!