BANGKOK - Thailand said on Monday it would start its coronavirus inoculation programme next month by administering 50,000 doses of AstraZeneca's vaccine to high-risk groups, as it faces accusations of being too slow to secure vaccines.

"We will start with medical personnel and high-risk individuals and areas," senior health official Sopon Mekton, told reporters.

Health workers in Samut Sakhon province, the epicentre of the latest outbreak, would be the first to be inoculated, then elderly and people with chronic diseases.

Thailand's food and drug administration last week approved AstraZeneca's vaccine for emergency use but has yet to grant authorisation for that of Sinovac Biotech, of which Thailand has ordered two million doses. 

Health Minister Anutin Charnvirakul on Monday said AstraZeneca would be supplying 50,000 fewer doses of the vaccine than the 200,000 Thailand had ordered.

"With the orders they have at hand, they just confirmed to us, they would supply 150,000 doses," Anutin told reporters, without elaborating, adding Thailand had initially requested one million doses.

Thailand has so far recorded only 13,687 infections and 75 coronavirus deaths.

The government has been criticised for taking too long to procure vaccines while neighbours in Southeast Asia start vaccinations or race to secure supplies from multiple companies. The government has rejected the criticism.

Thanathorn Juangroongruangkit, a prominent politician, has said the strategy relied too much on one company, Siam Bioscience, a firm under the holdings of King Maha Vajiralongkorn, which will manufacture the Astrazeneca vaccine locally for regional distribution. 

Two leaders of an anti-government protest movement held a small demonstration on Monday to protest what they said was preferential treatment for the Siam Bioscience.

Siam Bioscience has declined to comment on that allegation. Prime Minister Prayuth Chan-ocha on Monday reiterated the agreement was above board.

Siam Bioscience on Monday said it was altering its manufacturing plan to pour all available resources into producing the coronavirus vaccine and meeting AstraZenca's standards.

(Reporting by Chayut Setboonsarng, Patpicha Tanakasempipat and Panarat Thepgumpanat; Editing by Martin Petty) ((patpicha.tanakasempipat@tr.com; +6620802303 or mobile +66818317884; @patpichatan;))