BANGKOK: Trafficking of synthetic drugs in East and Southeast Asia continued to expand last year, with more than one billion methamphetamine tablets seized by authorities, the United Nations said on Monday.

Prices of methamphetamine or meth, by far the region's most popular drug, fell last year even as interceptions rose, indicating supply had surged, the U.N. Office of Drugs and Crime (UNODC) said in a report.

"The region is literally swimming in methamphetamine and I think it's high time that the region start taking a hard look at policies in place to address the problem," said Jeremy Douglas, UNODC Regional Representative for Southeast Asia and the Pacific.

While seizures of crystallized, liquid and powdered meth declined in 2021, tablet confiscation spiked, the report said.

Overall, authorities in Asia seized a record 171.5 tons of meth in 2021, up from 170 tonnes last year. More than 90% of the tablet seizures occurred in Thailand, Laos, Myanmar and Cambodia, where it is used both recreationally and by workers.

"There are a lot of seizures being made but no impact being made on the business itself. Organised crime just keeps cranking up the volume," said Douglas.

The report also noted a major change in trafficking routes from the centre of meth production in Myanmar's Shan State.

Laos registered a more than a 660% jump in interceptions of meth tablets in 2021, as increased anti-narcotic operations in Thailand and Southern China drove crime syndicates to enlarge their operations in northern Laos.

Laos was "a soft target for traffickers", Douglas said.

The report noted a record 2.7 tonnes of ketamine seizures in Cambodia, nearly fifteen times the amount seized in the previous five years combined.