Customs-based exports fell 10.9% in March from a year earlier, the Commerce Ministry said on Monday, weaker than analysts' expectations.
The reading compared with a forecast for a 4.5% year-on-year fall for March in a Reuters poll, and followed February's 3.6% rise.
Exports to China and Japan fell 9.7% and 19.3%, respectively in March, government data showed.
In the first three months of the year, exports fell 0.2%, but agriculture and computer parts will help shipments recover and expand up to 2% in the second quarter, Poonpong Naiyanapakorn, the director-general of the Trade Policy and Strategy Office, told a press conference.
Exports are a key driver of Southeast Asia's second-largest economy, which unexpectedly shrank 0.6% in the final quarter of 2023 from the third, prompting the state planning agency to cut its 2024 growth outlook to between 2.2%-3.2% from the 2.7%-3.7% earlier projected.
"We have to closely monitor geopolitical conflict and the global economy," he said.
The weak baht would also help exports recover.
If the baht remained around current levels it could help drive sales of auto parts, fruit and agriculture goods, said Chaichan Chareonsuk, chairman of the Thai National Shippers Council.