Mr Therdsak says the higher tariff burden could erode Thailand's competitive position in key export markets and slow shipment growth during the second half of the year, while Thailand's expanding trade surplus with the US increases the risk of additional US trade moves.

The US tariff of 12.5% imposed on Thailand could weaken export competitiveness and add pressure to economic growth in the second half, with further US trade measures still looming, warns Asia Plus Securities (ASPS).

Therdsak Taveeteeratham, executive vice-president at ASPS, said the export sector faces growing uncertainty after the US introduced new tariffs under its Section 301 trade measures, raising concerns over the country's competitiveness despite a strong recent export performance.

The 12.5% rate is higher than the 10% levy imposed on several regional peers such as the Philippines and Malaysia. The new tariffs could slow Thailand's export growth in the second half of the year, he noted.

"The higher tariff burden could erode Thailand's competitive position in key export markets and slow export growth during the second half of the year," said Mr Therdsak.