Thailand is considering accepting tens of thousands of foreign workers from Myanmar and other countries as factories reopen following a devastating flood crisis, an official said Thursday.

An estimated 120,000 workers -- both legal and illegal -- returned home to Myanmar because of the months-long disaster, a senior official at the Thai labour ministry, Anourak Tossarat, told AFP.

"We may be able to import workers from Myanmar either by land or air. The important thing is that they must come to Thailand legally," he said.

"My plan is to make Thailand free of illegal migrant workers and stop human trafficking."

Migrant communities were hit hard by the floods that swept across much of central and northern Thailand from July -- leaving more than 600 people dead, damaging millions of homes and inundating hundreds of factories.

Most of the workers who fled the kingdom have not returned and many flood-stricken production plants have yet to resume operations, so the scheme is not expected to be implemented before early 2012, he said.

Usually migrants enter Thailand by land -- often illegally -- and the idea of allowing them in by air was raised by the Thai government during a recent visit by Myanmar's deputy labour minister.

Anourak said the Myanmar side had "responded positively" to the idea but pointed out that by law its workers who travel overseas on a passport must pay a 10-percent income tax and the cost of flying is quite high.

He said the two countries were discussing who would pay for the flights.

"Normally, the workers are responsible for all expenses. But maybe the employers could help."

Migrant workers, who typically hold low-paid menial jobs, are a key driver of the Thai economy. The kingdom usually has a migrant workforce of up to about two million people, mostly from poorer neighbours Myanmar, Cambodia and Laos.

"But we're not limiting it to only these three countries. It could be any other country like Bangladesh or Nepal. If they enter Thailand legally, they can work in Thailand legally," Anourak said.

Activists say that workers travelling overland are vulnerable to trafficking and exploitation, including extortion by immigration officials and police.