BANGKOK - Thailand's unemployment rate fell in the fourth quarter of 2020 from the third quarter, as an easing of COVID-19 curbs led to a revival in economic activity, but a recent rise in infections poses a risk, the state planning agency said on Tuesday.

The unemployment rate was 1.86% in the October-December quarter, representing 730,000 workers without jobs, agency data showed, down from 1.90% in the September quarter. The rate hit an 11-year high of 1.95% in the June quarter.

"Employment increased slightly, while the unemployment rate remained high and working hours were still lower than pre-crisis levels," Danucha Pichayanan, head of the National Economic and Social Development Council, told a briefing.

The number of workers in Thailand's economy rose to 38.3 million in the fourth quarter of last year from 37.9 million in the previous quarter and from 37.5 million in the final quarter of 2019.

The increase took place mainly in farming, which benefited from higher crop prices and government projects.

But the jobless rate jumped to 1.69% last year, the highest level in at least 16 years, from 0.98% in 2019, as Southeast Asia's second-largest economy suffered its worst contraction in over two decades in 2020 as tourism slumped.

After managing to get its first coronavirus outbreak under control within a few months last year, Thailand is now dealing with a second wave that has slowed economic activity.

The latest coronavirus wave would hit businesses that had not yet recovered from the first outbreak, risking job cuts, Danucha said.

"If the virus cannot be controlled, combined with delays in the distribution of vaccines, the impact on the labour market and employment will be severe in the long run," he said.

Thailand will start vaccinating priority groups, including health workers, against COVID-19 later this week, with the country's first coronavirus vaccines due to arrive on Wednesday.

(Reporting by Kitiphong Thaichareon; writing by Orathai Sriring; editing by Ana Nicolaci da Costa, Larry King) ((orathai.sriring@tr.com; +662 0802309;))