About 500 women from Myanmar have been barred in the past three weeks from leaving their country to work in Singapore as maids, said employment agencies.
The Myanmar government has imposed a ban before, citing ill-treatment and abuse of maids.
"We used to have about 20 maids from Myanmar coming in every week," said Mr Gary Chin, managing director of Nation Employment. "Now, we have none."
At least 15 agencies have been affected, said Ms K. Jayaprema, president of the Association of Employment Agencies Singapore.
To skirt the ban, agencies tried to get the women in by applying for tourist visas or even flying them in through a third country, according to Chinese evening paper Shin Min Daily News. But the Myanmar government quickly saw through the tactics.
In September last year, its Labour Ministry expressed concern over the ill-treatment and abuse of maids and imposed a five-month ban, according to a Straits Times report.
But the women defied the ban and continued to come.
Last year, there were reportedly 30,000 maids from Myanmar working in Singapore. Myanmar is the third most popular source country - behind the Philippines and Indonesia - for domestic workers.
Women from Myanmar were not allowed to work here as maids until March last year, when their government stipulated that they had to receive a minimum monthly salary of $450 and get at least one day off a month, according to Myanmar newspaper reports. Their recruitment fees also could not exceed four months of their salary.
However, enforcement is difficult, said a spokesman for the Dynamic Maids agency.
The Myanmar embassy had not replied to queries by presstime.