More than 70,000 undocumented Cambodians have registered in new centres in Thailand in their first week of operation, though experts yesterday warned the designated two-week window will be too short for all migrants to register.

On June 23, the Thai government passed a new royal decree imposing hefty fines on undocumented migrants and their employers, but in apparent response to backlash from civil society and employers, postponed the implementation of the fines until December 31. In addition, it granted a two-week window – ending on Monday – for migrants and employers to register at temporary centres in each province and Bangkok.

Amnaj Sangsrikaew, an official at the Thai Labour Ministry’s Department of Employment, said that as of Monday, about 70,000 Cambodian workers had registered since the creation of 97 new centres on July 24. Data published on the Labour Ministry’s website late yesterday, however, put the number at 80,851 Cambodians registered among a total of 288,954 migrants.

Mom Sokchar, programme manager at Legal Support for Children and Women, said the time granted was too short.

“I don’t think all migrants can register,” he said, adding that migrants also had to rely on employers. “If the employer doesn’t [want them to] register, how can the migrants get documented?”

Read more: Voices from the Thai border

Dy The Hoya, of labour rights group Central, said that once the deadline passed, the only way to get documented was to return to Cambodia. “In that case the employers do not have enough workers,” he said. “The Cambodian and Thai governments have to extend the deadline.”

Barry Jessen, senior manager at Samaritan’s Purse, echoed this assessment. “Seventy thousand is a large number – but the estimates [about the number of undocumented workers] are much, much higher than that,” he said. “If they don’t register, they have to keep their heads down and hide.”

He said there were at least 500,000 undocumented Cambodian workers in Thailand, and added that the registration alone wasn’t sufficient – they had to get passports and travel documents, for which the Cambodian Embassy was responsible.

“If these 500,000 irregular workers are heading home, employers will be 500,000 workers short, which is where we were in 2014,” he said, referring to a mass exodus of migrants caused by a previous crackdown. “And no one wants that.”

The Cambodian Embassy, the Ministry of Foreign Affairs, and Cambodian Labour Ministry spokesperson Heng Sour could not be reached yesterday.