Thailand plans to ask South Korea to consider granting illegal Thai migrant workers already in South Korea temporary permission to work, so that not all of the approximately 120,000 workers will have to return home.

Labour Minister Adul Sangsingkeo revealed the plan after a meeting on Wednesday to discuss the problem of the high number of illegal Thai migrant workers in South Korea.

South Korea's quota of 5,000 Thai workers per year is not enough to meet the demand among Korean employers for Thai workers, said Pol Gen Adul.

Thai workers are attracted by high pay of between 40,000 and 50,000 baht a month in South Korea, while South Korean employers still need to hire more Thai workers than those allowed to visit on a work visa, he said.

"These are the key factors that contribute to the rising number of illegal Thai migrant workers there," he said.

The meeting also concluded that most Thais who become illegal migrant workers in South Korea failed the mandatory Korean language test. Furthermore, while South Korea limits the maximum age of workers allowed to work in South Korea to 39, the majority of Thai workers who intend to go to South Korea are older, he said.

Also, although more female Thai workers pass the Korean language test than their male counterparts, Korean employers prefer to hire male workers, he added.

Pol Gen Adul previously led a delegation to South Korea to talk to labour and justice officials about potential solutions to the increasing number of Thai nationals who overstay their visas and become illegal migrant workers.

Following the talks, South Korea announced a voluntary departure programme for about 300,000 illegal migrant workers, including 120,000 Thais, starting on Oct 1 and ending on March 31 next year. During this period, illegal migrants will be pardoned and will not be blacklisted by South Korean immigration authorities.

Thai Labour Attache to South Korea, Pinyuda Chamchansri, said the Royal Thai Embassy in Seoul is speeding up dissemination of information about the voluntary departure programme through Thai labour networks in South Korea. A number of inquiries about the details of the programme have been received from a number of illegal Thai migrant workers through Facebook and by phone, she said.

She said South Korean immigration authorities plan to begin cracking down on illegal migrant workers at work locations such as construction sites, entertainment venues and traditional massage parlours on Nov 1. While they are being given a waiver from the threat of immediate legal action, they do have to leave the country.

Pol Gen Adul asked Thai labour officials to begin contacting their South Korean counterparts to see if they will reconsider the demand that 120,000 illegal Thai workers leave during the voluntary departure period.

A request to extend the maximum work permit length from nine to 14 years, and raise the workers' age ceiling above 39 have already been submitted, he said. In Thailand, a centre will be set up to handle workers who return to the country under the pardon programme.