Thailand's Prime Minister Prayuth Chan-ocha has said the country will speed up vaccinations and introduce urgent stimulus measures to mitigate the impact of its most severe coronavirus outbreak.

Thailand has reported more than 1.5 million infections and 15,000 deaths, about 99 per cent of those since April this year, after a year of successful containment during which its key tourism sector collapsed, Reuters reports.

The government expects the situation to normalise quickly, Prayuth Chan-ocha told a news conference hosted by the state planning agency.

"The government will make full efforts to resolve the crisis so that people can return to normal life as soon as possible," he said.