Walk-in vaccinations will be part of a blanket, three-channel Covid-19 inoculation campaign to be launched by the government from June 1.
Public Health Minister Anutin Charnvirakul said each province will be responsible for the management of the vaccine supplies to be distributed by his ministry's Department of Communicable Disease.
He insisted that no province will get preferential treatment, pointing out that provincial governors would have to submit their vaccine requests.
Traisuree Taisaranakul, deputy spokeswoman for the government, said Prime Minister Prayut Chan-o-cha wants to inoculate as many people as possible to minimise the risk of infection, severe illness and fatalities.
The national committee on vaccination resolved on May 12 that vaccinations would be provided through three channels, including walk-in services, Ms Traisuree said.
Preparations are now being made to put this plan into action, she said.
Different provinces are at different levels of readiness, and information coming from them could be confusing, the spokeswoman said.
Gen Prayut is reportedly concerned about this and has instructed local authorities to do a better job of informing the people.
Meanwhile, the government had lifted its target from procuring 100 million doses of coronavirus vaccines to 150 million doses so there would be enough for everybody, Ms Traisuree said.
Blanket vaccinations would begin in June through three channels -- online registration via the Mor Prom (Doctors Ready) app; group registration through public health volunteers or other groups of officials, or private companies; and walk-ins by people, she said.
Vaccines would be distributed through the three channels in the ratio of 30:50:20, respectively. However, this could be adjusted by provincial disease control committees, Ms Traisuree said.
"Walk-in services for vaccination will certainly be opened so that people who could not register online or did not make an appointment can still be inoculated," she said.
"However, walk-in services will depend on the readiness of each area. The quantity of vaccine available and the virus situation must also be taken into consideration in each area, such as in Bangkok."