The Fiscal Policy Office (FPO) has kept its forecast for economic growth this year at an average of 3.5%, underpinned by a recovery in both the tourism sector and domestic consumption, according to the office's director-general Pornchai Thiraveja.
The office reviews the GDP forecast every three months.
The state agency has also revised upward its projection of the number of foreign tourist arrivals this year to 8 million, up from the prediction of 6.5 million made in April.
Last year the number of foreign arrivals stood at around 400,000.
Mr Pornchai added that the higher number of tourist arrivals this year has boosted household income and supported the recovery of the tourism and related sectors.
The FPO forecast for the higher number of foreign tourist arrivals this year has yet to take into account the Chinese government's plan to allow people living in China's southern area to travel abroad, Mr Pornchai said.
He added that this would further boost Thailand's GDP growth.
The state agency also upgraded its growth projection of private consumption this year to 4.8%, up from the April forecast at 4.3%.
The prediction is close to estimates of other state economic agencies, he added.
The FPO expects the export value to expand 7.7% year-on-year this year, higher than its April forecast of 6%, despite the impact of the Russia-Ukraine war.
He added that this latest FPO forecast on exports is close to that of the National Economic and Social Development Council's figure of 7.3%.
Private investment is expected to expand 5.7% this year, compared to the 4.5% growth it projected in April, in line with the economic recovery.
Foreign direct investment in Thailand in the first quarter of this year rose 23% year-on-year to US$5.4 billion.
The state agency projects the headline inflation of 6.5% this year due to the rising energy price.
The headline inflation last year was 1.2%.
Mr Pornchai added that among the factors that could impact the economy are the recovery of local demand due to the improvement of the Covid-19 pandemic situation, the number of foreign tourist arrivals and the impact of the ongoing Russia-Ukraine war.